2510.13999

# REAP the Experts: Why Pruning Prevails for One-Shot MoE compression **Authors**: - Yani Ioannou, Vithursan Thangarasa (Cerebras Systems Inc., Schulich School of Engineering, University of Calgary) Abstract Sparsely-activated Mixture-of-Experts (SMoE) models offer efficient pre-training and low latency but their large parameter counts create significant memory overhead, motivating research into expert compression. Contrary to recent findings favouring expert merging on discriminative benchmarks, we demonstrate that expert pruning is a superior strategy for generative tasks. We prove that merging introduces an irreducible error by causing a “functional subspace collapse”, due to the loss of the router’s independent, input-dependent control over experts. Leveraging this insight, we propose Router-weighted Expert Activation Pruning (REAP), a novel pruning criterion that considers both router gate-values and expert activation norms. Across a diverse set of SMoE models ranging from 20B to 1T parameters, REAP consistently outperforms merging and other pruning methods on generative benchmarks, especially at 50% compression. Notably, our method achieves near-lossless compression on code generation and tool-calling tasks with Qwen3-Coder-480B and Kimi-K2, even after pruning 50% of experts. Correspondence to mklasby@ucalgary.ca & vithu@cerebras.net $\dagger$ Work completed while on internship at Cerebras | <details> <summary>2510.13999v1/x1.png Details</summary>  ### Visual Description Icon/Small Image (25x24) </details> | https://github.com/CerebrasResearch/reap | | --- | --- | | <details> <summary>2510.13999v1/x2.png Details</summary>  ### Visual Description Icon/Small Image (26x24) </details> | https://hf.co/cerebras/Qwen3-Coder-REAP-363B-A35B-FP8 | | <details> <summary>2510.13999v1/x3.png Details</summary>  ### Visual Description Icon/Small Image (26x24) </details> | https://hf.co/cerebras/Qwen3-Coder-REAP-246B-A35B-FP8 | 1 Introduction Interest in the Sparsely-activated Mixture-of-Experts (SMoE) architecture for Large Language Models (LLMs) surged following the release of DeepSeek-V3 (DeepSeek-AI et al., 2024) and other high-quality open-weight SMoE LLMs (Jiang et al., 2024; Meta AI Team, 2025; Yang et al., 2025a; Zeng et al., 2025; Baidu, 2025; Kimi Team et al., 2025). Compared to dense models, the SMoEs offer lower latency and more efficient pre-training (Fedus et al., 2022). However, SMoEs require more parameters than dense models to achieve similar accuracy, resulting in significant memory overhead. Further, expert usage imbalance during inference causes poor accelerator utilization, leading to increased latency or compromises such as dropped tokens (Balmau et al., 2025). Expert usage imbalance also represents an opportunity, motivating prior work which investigates whether experts can be compressed without negatively impairing accuracy (Li et al., 2023; Lu et al., 2024). By eliminating or compressing redundant experts, memory overhead is reduced. A more uniform distribution of expert usage would also improve hardware utilization. Expert compression is particularly valuable for use cases which feature small batch sizes such as local deployments and academic research. Initial expert compression efforts focused on expert pruning, the removal of experts in their entirety. However, expert pruning is a strong intervention on the model’s weights. Techniques such as quantization, low-rank compression, and expert merging also offer memory savings but maintain a lossy representation of the less important experts. Crucially, expert merging has recently been demonstrated to outperform expert pruning when evaluated with perplexity and on Multiple Choice (MC) question answering benchmarks (Li et al., 2023; Liu et al., 2024b). However, an evaluation comparing these methods on generative benchmarks has yet to be conducted. In this work, we demonstrate that — when paired with a suitable saliency criterion — expert pruning outperforms expert merging, particularly on generative benchmark tasks such as code generation, creative writing, and mathematical reasoning. Specifically, our main contributions are as follows: - We prove that expert merging introduces irreducible error due to the loss of the router’s independent, input-dependant modulation of the expert outputs resulting in functional subspace collapse, substantially reducing the functional output space of the compressed SMoE layer. In contrast, in expert pruned SMoEs the router maintains independent control over the remaining experts; - We introduce Router-weighted Expert Activation Pruning (REAP), a novel expert pruning saliency criterion, which selects experts to prune which contribute minimally to the layer output by considering both the router gate-values and average activation norm of the experts; - Across diverse SMoE architectures ranging from 20B to 1T parameters and a suite of generative evaluations, we demonstrate the significant and consistent advantage of REAP over existing expert pruning and merging approaches, particularly at 50% compression. Notably, our method achieves near-lossless compression on code generation tasks after pruning 50% of experts from Qwen3-Coder-480B and Kimi-K2; - We open-source our code and select compressed model checkpoints to facilitate further research on compressed SMoEs and their applications. 2 Related Work Sparsely activated SMoE architecture. A Mixture-of-Experts (MoE) layer is comprised of multiple, specialized feed-forward subnetworks known as experts and a router which produces gate-values (i.e., gates) to dynamically modulate the output of the experts based on the input. The architecture was revived in the deep learning era by the introduction of the SMoE by Shazeer et al. (2017). SMoEs layers only select a subset of experts to use for each input, enabling massive scaling of model parameters without a commensurate increase in computational cost (Lepikhin et al., 2021; Fedus et al., 2022). In transformer-based LLMs, SMoE layers are integrated by replacing the traditional feed-forward layers. Further innovations such as auxiliary-loss-free load balancing (DeepSeek-AI et al., 2024), shared experts, and fined-grained experts (Dai et al., 2024) have propelled SMoE architectures to become the de facto standard for LLMs in recent months. Expert pruning. Although SMoE layers effectively decouple total model parameters from inference costs, the memory overhead of storing large SMoEs restricts their deployment in resourced-constrained environments, motivating research in expert pruning to reduce total number of parameters. Early efforts demonstrated that progressively pruning experts based on router weights during fine-tuning until a single expert remained could preserve model quality in task-specific settings (Chen et al., 2022). Koishekenov et al. (2023) found expert pruning to be effective without further fine-tuning despite aggressively pruning up to 80% of experts. Muzio et al. (2024) found that global pruning using gate-values as a saliency criterion was more effective than uniform, layer-wise frequency-based pruning. Other sophisticated pruning criteria have been proposed: Lu et al. (2024) introduced an exhaustive search strategy which prunes experts that minimize the reconstruction loss between the original and pruned layer outputs; Liu et al. (2024a) used a gradient-free evolutionary algorithm to prune experts. Both of these works demonstrated significant improvements over naive frequency-based pruning. A comprehensive evaluation of 16 diverse pruning criteria was conducted by Jaiswal et al. (2025). Expert Activation Norm (EAN) was empirically found to be the highest performing criterion and the benefits of iterative pruning were presented. Expert merging. While the above-noted works prove that expert compression is feasible via pruning, an alternative compression technique is to merge experts. Generally, merging requires both a clustering algorithm and a merging technique. Li et al. (2023) introduced Merge Sparse Mixture of Experts (M-SMoE) which first initializes expert cluster centres by identifying the dominant experts with the highest usage frequency globally across all layers. The remaining non-dominant experts are clustered based on the cosine similarity of router logits. Finally, experts weights are aligned via permutation with the weight matching algorithm (Ainsworth et al., 2023) and merged using frequency-weighted parameter averaging. Li et al. (2023) found that their technique outperformed Chen et al. ’s (2022) pruning method on MC benchmarks. Chen et al. (2025) proposed Hierarchical Clustering for Sparsely activated Mixture of Experts (HC-SMoE). HC-SMoE clusters experts based on the euclidean similarity of their representative vectors — the average activation of each expert measured on every token in a calibration dataset — using hierarchical agglomerative clustering. Similar to M-SMoE, HC-SMoE uses frequency-weighted parameter averaging to merge clusters into a single merged expert. Without any fine-tuning, Chen et al. (2025) found that their technique outperformed expert pruning based on router logits (He et al., 2025a), frequency, and Lu et al. ’s (2024) method when benchmarked on a suite of MC question answering tasks. Other compression techniques. In addition to pruning and merging, experts may be compressed through quantization (Huang et al., 2025), low-rank decomposition (Yang et al., 2024a; Gu et al., 2025; He et al., 2025b), weight sparsity (He et al., 2025a), or a combination of any of the above techniques (Liu et al., 2025). These other approaches are orthogonal to expert pruning and merging; however, note that expert merging necessitates re-quantization for block quantization formats that share common scaling coefficients across a group of weights. Model merging. Model merging aims to combine parameters from multiple trained neural networks and has been rapidly adopted as a cost-effective way to improve model quality across diverse domains. The initial motivation for merging was based on the finding that mode connectivity exists between the loss landscapes of two or more trained neural networks, enabling interpolation of their parameters without incurring an increase in loss (Garipov et al., 2018; Ainsworth et al., 2023; Ito et al., 2024). Simple parameter averaging remains an effective technique; however, more sophisticated strategies based on task vectors have also been proposed to minimize interference in the merged model parameters (Ilharco et al., 2023; Yadav et al., 2023; Yu et al., 2024). Much of the existing literature focuses on the setting in which multiple fine-tunes of a single checkpoint are merged. Non-local merging in which the models do not share a common checkpoint is more closely related to expert merging. Sharma et al. (2024) found that re-scaling of model activations was necessary to achieve high-quality non-local merging. LLM evaluation. Evaluating LLMs is challenging; prior work demonstrated that simple metrics such as perplexity can be misleading when used to evaluate compressed LLMs (Jaiswal et al., 2024). MC benchmarks typically measure the log-likelihood of answer tokens to determine a model’s response to a question (Gao et al., 2023; Chandak et al., 2025). As such, each response choice is evaluated in a single forward pass, without any tokens being generated by the model. Perplexity and MC accuracy can therefore be viewed as discriminative metrics. In contrast, generative benchmarks require the model to output a response, more closely corresponding with real-world use-cases of LLMs. Tasks such as code generation, mathematical reasoning with structured outputs, and creative writing are examples of generative benchmarks. 3 Merging Experts Causes Functional Subspace Collapse Setup. To motivate our proposed expert pruning method, we first formally develop the expected errors of both expert merging and pruning. Consider a SMoE layer with $K$ experts $f_{1},...,f_{K}$ , each a function $f_{k}:\mathbb{R}^{d}→\mathbb{R}^{d}$ , and a router producing non-negative gates $\mathbf{g(x)}=(g_{1}(x),...,g_{K}(x))∈\Delta^{K-1}$ . Top- $k$ routing is achieved by zeroing all but the largest $k$ gates. The output of the original layer is $$ h(x):=\sum_{k=1}^{K}g_{k}(x)\,f_{k}(x). \tag{1} $$ Two operations at fixed compression. To analyse the fundamental difference between compression operations, we focus on the elementary case of reducing two experts, $(f_{i},f_{j})$ , to one. This pairwise analysis is the building block for any larger merge within a cluster. Pruning removes expert $j$ and re-normalizes the router outputs over the remaining $K-1$ experts, producing a new set of gates $\bar{g}(x)$ . Merging replaces $(f_{i},f_{j})$ with a new expert $\tilde{f}$ . Existing one-shot expert merging methods such as HC-SMoE and M-SMoE sum the gates for the original experts $g_{i}(x)+g_{j}(x)$ . The pruned, $\bar{h}(x)$ , and merged, $\tilde{h}(x)$ , layer outputs are $$ \bar{h}(x):=\sum_{k\neq j}\bar{g}_{k}(x)\,f_{k}(x), \tag{2} $$ $$ \tilde{h}(x):=\sum_{k\neq i,j}g_{k}(x)f_{k}(x)+\big(g_{i}(x)+g_{j}(x)\big)\tilde{f}(x). \tag{3} $$ 3.1 Merging induces an input-dependent target a single expert cannot realize Define the router’s input-dependent mixing ratio $r(x):=\frac{g_{i}(x)}{g_{i}(x)+g_{j}(x)}∈[0,1]$ on the set where $g_{i}+g_{j}>0$ . Substituting $g_{i}(x)$ and $g_{j}(x)$ in terms of $r(x)$ , the original contribution of the pair $(i,j)$ can be written as $$ \displaystyle g_{i}(x)f_{i}(x)+g_{j}(x)f_{j}(x) \displaystyle=\big[r(x)(g_{i}(x)+g_{j}(x))\big]f_{i}(x)+\big[(1-r(x))(g_{i}(x)+g_{j}(x))\big]f_{j}(x) \displaystyle=\big(g_{i}(x)+g_{j}(x)\big)\underbrace{\Big(r(x)f_{i}(x)+\big(1-r(x)\big)f_{j}(x)\Big)}_{\text{The ideal, input-dependent target expert}}. \tag{4} $$ After merging, the router must apply the summed gate, $g_{i}(x)+g_{j}(x)$ , to a constant convex combination of the constituent experts which is independent of $x$ . The core issue is that the merged model is forced to approximate the dynamic, input-dependent target expert with a static one. The following theorem quantifies this unavoidable approximation error. **Theorem 1 (Irreducible error of merging)** *Let $\tilde{f}_{\alpha}(x)=\alpha f_{i}(x)+(1-\alpha)f_{j}(x)$ with a constant $\alpha∈[0,1]$ and define $\Delta_{ij}:=f_{i}(x)-f_{j}(x)$ . The $L^{2}$ error of the merged pair is minimized when $\alpha$ is chosen to be the expected mixing ratio, $\alpha^{\star}:=\mathbb{E}[r(x)]$ . Omitting the argument $(x)$ for brevity, this minimal error is $$ \displaystyle\big\|\,\big(g_{i}{+}g_{j}\big)\!\big(rf_{i}{+}(1{-}r)f_{j}\big)\;-\;\big(g_{i}{+}g_{j}\big)\!\big(\alpha f_{i}{+}(1{-}\alpha)f_{j}\big)\big\|^{2} \displaystyle=\underbrace{\mathbb{E}\!\left[(g_{i}{+}g_{j})^{2}\right]}_{\text{router scale}}\cdot\underbrace{\mathrm{Var}[r(x)]}_{\text{policy variability}}\cdot\underbrace{\|\Delta_{ij}\|^{2}}_{\text{expert gap}}. \tag{5} $$ In particular, if the router’s policy is not constant ( $\mathrm{Var}[r(x)]>0$ ) and the experts are not functionally identical ( $\|\Delta_{ij}\|>0$ ), then every constant- $\alpha$ merge incurs strictly positive excess risk.* * Proof* The error term simplifies to $\big\|\big(g_{i}{+}g_{j}\big)\big(r-\alpha\big)\Delta_{ij}\big\|^{2}$ . Assuming independence between the router policy and expert functions, this is proportional to $\mathbb{E}[(r-\alpha)^{2}]$ . This is a standard least-squares problem minimized when $\alpha=\mathbb{E}[r]$ , and the minimal value is $\mathrm{Var}[r]$ . ∎ Consequences. Theorem 1 illustrates that merging with summed gates is fundamentally flawed whenever (i) the router has learned an input-dependent policy for mixing two experts ( $\mathrm{Var}[r]>0$ ), and (ii) the experts are themselves distinct ( $\|\Delta_{ij}\|>0$ ). Any fixed $\alpha$ cannot overcome the irreducible error bound established in equation 5. 3.2 Pruning preserves independent control Pruning removes one function but importantly does not tie the remaining gates. The router still modulates each surviving expert independently. In contrast, merging removes a degree of freedom in the policy by replacing individual experts with their mergers. For a direct comparison under no fine-tuning, pruning expert $j$ and reallocating its gate-value to expert $i$ produces the error $$ \big\|(g_{i}(x)f_{i}(x)+g_{j}(x)f_{j}(x))-(g_{i}(x){+}g_{j}(x))f_{i}(x)\big\|^{2}\;=\;\mathbb{E}\!\left[g_{j}(x)^{2}\,\|\Delta_{ij}(x)\|_{2}^{2}\right]. \tag{6} $$ Unlike equation 5, equation 6 does not penalize policy variability, the router still controls surviving experts independently. Whenever the router substantially mixes $i$ and $j$ (large $\mathrm{Var}[r]$ ) while the pruned expert $j$ has a small average gate-value ( $\mathbb{E}[g_{j}^{2}]$ ), pruning admits a strictly smaller error than merging. Synthesis. Theorem 1 establishes that summed gate merging incurs an irreducible error directly proportional to the router’s policy variability ( $\mathrm{Var}[r(x)]$ ). In contrast, the error from pruning a low-usage expert (Eq. 6) is proportional to its gate-value ( $\mathbb{E}[g_{j}^{2}]$ ) and is insensitive to policy variability. Therefore, when the router actively mixes between two distinct experts, merging is fundamentally disadvantaged. Remarks. (i) The constant-mixture model $\tilde{f}_{\alpha}$ is mathematically related to the frequency weighted parameter averaging merge used in practice. (ii) Even if $\tilde{f}$ was dependent on $x$ , the router after merging cannot independently modulate the two latent functions, so the original policy is invalidated. (iii) With top-k routers, the specific irreducible error from policy variability ( $\mathrm{Var}[r(x)]$ ) is generated exclusively on the support where both experts are selected. Outside that support, this component vanishes, leaving only a static error term that depends on the functional expert gap. (iv) See Appendix ˜ A for an extension of the above analysis to hierarchical clustering. 3.3 Empirical evidence for loss of independent control Setup. We analyse the functional subspaces of expert outputs across four diverse state-of-the-art SMoE architectures by recording mean expert activations from 32 samples of 2048 tokens from the c4 dataset (Raffel et al., 2020). By projecting expert activations onto their first two principal components, we visualize how pruning and merging affect the learned representations. See Appendix ˜ B for additional discussion. Early vs. late behaviour. Figures ˜ 1 and A4 demonstrate a striking progression of functional collapse from early to late layers across all architectures. In early layers, the original experts form relatively compact manifolds with moderate spread. After pruning, the surviving experts maintain their positions on the original manifold, preserving its geometric structure with reduced density. In contrast, merging produces a visible contraction toward the manifold’s centre. The contrast becomes dramatic in late layers, where experts are more specialized, and in high granularity architectures with many experts per layer. The progression from early to late layers validates our theoretical prediction that the irreducible error is proportional to $\mathrm{Var}[r(x)]$ . Early layers, which typically learn more generic features, exhibit lower policy variability and thus less dramatic collapse. Late layers, where experts have specialized for distinct computational roles, demonstrate high policy variability, resulting in the severe functional collapse observed when these specialized experts are merged into static averages. Synthesis across architectures. The consistency of these patterns across architectures with vastly different expert counts (8 to 128), sparsity levels (6.25% to 25% active), and parameter scales (21.9B to 109B) demonstrates that functional collapse under merging is a fundamental property of the operation rather than an artifact of specific implementations. These visualizations reveal that the core issue is not the reduction in the number of experts per se, but rather the qualitative change in the router’s control structure. <details> <summary>2510.13999v1/x4.png Details</summary>  ### Visual Description # Technical Document Extraction: Scatter Plot Analysis ## Image Description The image contains three scatter plots arranged horizontally, each representing different data groupings. The plots are labeled with titles, axes, and a legend. The data points are color-coded to distinguish categories. --- ## Key Components ### 1. **Plot Titles** - **Left Plot**: "Original Experts" - **Middle Plot**: "Surviving" - **Right Plot**: "Merged" ### 2. **Axis Labels** - **X-axis**: "PC1" (Principal Component 1) - **Y-axis**: "PC2" (Principal Component 2) ### 3. **Legend** - **Colors and Labels**: - **Red**: "Original Experts" - **Blue**: "Surviving" - **Green**: "Merged" - **Gray**: Unlabeled (appears in "Surviving" and "Merged" plots) ### 4. **Axis Ranges** - **PC1**: -0.5 to 0.5 - **PC2**: -1.0 to 0.0 --- ## Data Trends and Observations ### **Original Experts (Red Points)** - **Cluster**: Points are densely clustered around the origin (PC1 ≈ 0, PC2 ≈ 0). - **Spread**: Some points extend slightly to the left (PC1 < 0) and downward (PC2 < 0). - **Notable**: No gray points present in this plot. ### **Surviving (Blue and Gray Points)** - **Blue Points**: Clustered in the upper-left quadrant (PC1 ≈ -0.2, PC2 ≈ 0.2). - **Gray Points**: Scattered across the plot, with some near the origin and others in the lower-right quadrant. - **Observation**: The blue cluster is distinct from the gray points, suggesting a separation in the "Surviving" category. ### **Merged (Green and Gray Points)** - **Green Points**: Clustered in the upper-right quadrant (PC1 ≈ 0.2, PC2 ≈ 0.2). - **Gray Points**: Scattered, with some overlapping the green cluster and others in the lower-left quadrant. - **Observation**: The green cluster is distinct from the gray points, indicating a merged category with potential overlap or noise. --- ## Cross-Reference: Legend vs. Plot Data - **Red (Original Experts)**: Matches the left plot's red points. - **Blue (Surviving)**: Matches the middle plot's blue points. - **Green (Merged)**: Matches the right plot's green points. - **Gray**: Appears in both "Surviving" and "Merged" plots but is not explicitly labeled in the legend. Likely represents a subset or noise category. --- ## Summary The three plots visualize principal component analysis (PCA) results for three categories: "Original Experts," "Surviving," and "Merged." The "Original Experts" cluster tightly around the origin, while "Surviving" and "Merged" show distinct clusters with additional gray points that may represent noise or subcategories. The gray points in "Surviving" and "Merged" plots are not explicitly labeled in the legend, suggesting they may be a separate or unclassified group. </details> (a) Qwen3-30B Layer 0 <details> <summary>2510.13999v1/x5.png Details</summary>  ### Visual Description # Technical Document Extraction: PCA Visualization of Expert Groups ## Overview The image presents three scatter plots visualizing Principal Component Analysis (PCA) results for three distinct groups: **Original Experts**, **Surviving**, and **Merged**. Each plot uses 2D PCA components (PC1 and PC2) to represent multidimensional data in a reduced dimensionality space. --- ### **1. Original Experts** **Legend Color**: Red (`#FF6B6B`) **Spatial Grounding**: - PC1 axis: -200 to 200 - PC2 axis: -150 to 50 **Key Observations**: - **Trend**: Points exhibit a dispersed distribution across the entire plot area. - **Data Points**: - Clustered primarily in the upper-left quadrant (PC1: -100 to 0, PC2: 0 to 50). - Outliers extend to PC1 ≈ -150 (PC2 ≈ -150) and PC1 ≈ 200 (PC2 ≈ 50). - **Interpretation**: High variability in the original expert group, with no clear central tendency. --- ### **2. Surviving** **Legend Color**: Blue (`#4ECDC4`) **Spatial Grounding**: - PC1 axis: -200 to 200 - PC2 axis: -150 to 50 **Key Observations**: - **Trend**: Points form a loose cluster centered around PC1 ≈ 0, PC2 ≈ 0. - **Data Points**: - Concentrated between PC1: -50 to 50 and PC2: -50 to 50. - Some outliers extend to PC1 ≈ -100 (PC2 ≈ -100) and PC1 ≈ 100 (PC2 ≈ 0). - **Interpretation**: Reduced variability compared to "Original Experts," suggesting a subset of retained data points. --- ### **3. Merged** **Legend Color**: Green (`#7FDB6A`) **Spatial Grounding**: - PC1 axis: -200 to 200 - PC2 axis: -150 to 50 **Key Observations**: - **Trend**: Points form a dense, compact cluster in the upper-right quadrant. - **Data Points**: - Clustered tightly between PC1: 0 to 100 and PC2: 0 to 50. - No significant outliers. - **Interpretation**: High cohesion in the merged group, indicating strong alignment in the reduced-dimensional space. --- ### **Legend and Axis Labels** - **Legend**: - Red: Original Experts - Blue: Surviving - Green: Merged - **Axes**: - X-axis: PC1 (Principal Component 1) - Y-axis: PC2 (Principal Component 2) --- ### **Cross-Reference Validation** - **Color Consistency**: - Red points in "Original Experts" match the legend. - Blue points in "Surviving" match the legend. - Green points in "Merged" match the legend. - **Axis Alignment**: All plots share identical PC1/PC2 axis ranges, ensuring comparability. --- ### **Conclusion** The PCA visualization demonstrates: 1. **Original Experts**: High dispersion with no clear pattern. 2. **Surviving**: Moderate clustering around the origin. 3. **Merged**: Tight clustering in the upper-right quadrant, suggesting optimal alignment post-merging. This analysis supports hypotheses about data reduction and group differentiation in the dataset. </details> (b) Qwen3-30B Layer 47 Figure 1: (1(a)) Functional subspace (PCA) for early SMoE layers in Qwen3-30B. Pruning (blue) preserves the manifold geometry; merging (green) collapses it toward the centre. (1(b)) Functional subspace (PCA) for late MoE layers. The contraction under merging is dramatically more pronounced, with up to 100 $×$ reduction in spread for models with many experts. See Figure ˜ A4 for results from other models. 4 Router-weighted Expert Activation Pruning (REAP) The above analysis demonstrates that the functional output space of a SMoE layer is defined by the coordinated behaviour of the router and experts. An expert’s total contribution to its layer’s output is determined by both its gate-value, $g_{k}(x)$ , and the magnitude of its output vector, $\big\|f_{k}(x)\big\|_{2}$ . However, naive frequency-based pruning fails to consider these properties. Intuitively, pruning experts which contribute minimally to the layer output minimizes the difference between the original and pruned layer outputs. Let $h(x)$ be the original output and $\bar{h}_{\setminus j}(x)$ be the output after pruning expert $j$ and re-normalizing the remaining router weights. The error induced by pruning expert $j$ is $$ \Delta\bar{h}_{\setminus j}(x):=h(x)-\bar{h}_{\setminus j}(x)=\sum_{k}g_{k}(x)f_{k}(x)-\sum_{k\neq j}\frac{g_{k}(x)}{1-g_{j}(x)}f_{k}(x). \tag{7} $$ Re-normalization of the router weights after pruning expert $j$ modulates all other remaining expert outputs, making direct minimization of $\Delta h_{j}$ complex. However, since our goal is to prune unimportant experts, we can reasonably assume their gate-values are small when active $\mathbb{E}_{x\sim\mathcal{X}}[g_{j}(x)]\ll 1$ . Under this assumption, the weight re-normalization factor is negligible, i.e., $1-g_{j}(x)≈ 1$ , and the error induced by pruning expert $j$ is approximately equal to the expert’s direct contribution to the layer output $$ \Delta\bar{h}_{\setminus j}(x)\approx\sum_{k}g_{k}(x)f_{k}(x)-\sum_{k\neq j}g_{k}(x)f_{k}(x))=g_{j}(x)f_{j}(x). \tag{8} $$ To select which experts to prune, we propose a novel saliency criterion, REAP, which approximates an expert’s importance by measuring its direct contribution to the layer’s output magnitude. Specifically, the saliency score, $S_{j}$ , is defined as the average of this contribution over tokens for which the expert is active where $S_{j}$ is the saliency of expert $f_{j}$ and $\mathcal{X}_{j}$ is the set of inputs where $g_{j}(x)∈ TopK(\mathbf{g(x))}$ . $$ S_{j}=\frac{1}{|\mathcal{X}_{j}|}\sum_{x\in\mathcal{X}_{j}}g_{j}(x)\cdot\big\|f_{j}(x)\big\|_{2}, \tag{9} $$ where $\mathcal{X}_{j}$ is the set of tokens where expert $j$ is active (i.e., $\mathcal{X}_{j}=\{x\mid j∈\text{TopK}(\mathbf{g}(x))\}$ ). The experts with the minimum saliency score are selected for pruning. REAP is robust to outlier activations and has a direct, intuitive interpretation by quantifying the average magnitude an expert adds to the output vector when it is selected by the router. Pruning experts with the lowest $S_{j}$ removes those with the least impactful contribution. 5 Experiments Setup. We implement REAP and other expert compression baselines in PyTorch (Ansel et al., 2024). We collect router logits and expert activation data to calibrate the compression algorithms using a variety of general pre-training and domain-specific Supervised Fine-Tuning (SFT) datasets. For calibration, 1,024 samples are randomly selected and packed to 2,048 sequence length for models with $≤$ 110B parameters. For models with $≥$ 110B parameters, we select 12,228 samples with a maximum sequence length of 16,384 tokens without truncation or packing. We compress models by pruning or merging 25% or 50% of experts in each layer, except for M-SMoE which determines the number of clusters per layer based on global expert usage frequency. When evaluating models with $≤$ 50B parameters on coding and MC, we calibrate and compress the models using three different seeds and report the mean. Larger models, creative writing, and mathematical reasoning evaluations are reported using a single seed, except where explicitly noted otherwise. All models are evaluated in the one-shot setting, with no additional fine-tuning after compression. Models and data. We evaluate the expert compression algorithms on a diverse set of six SMoE architectures covering model sizes from 21B to 1T with varying degrees of sparsity and expert granularity, see Table ˜ 1 for details. For MC question answering and code generation benchmarks, we use c4 (Raffel et al., 2020; Allen Institute for AI, 2024) and evol-codealpaca (Chaudhary, 2023; Luo et al., 2024; Tam, 2023) datasets to assess both general and domain-specific calibration. Models with $≥$ 110B parameters are additionally calibrated with data from xlam-function-calling (Liu et al., 2024c; Salesforce, 2025) and SWE-smith-trajectories (Yang et al., 2025c; b) datasets. For creative writing and math benchmarks we employ WritingPrompts curated (Pritsker, 2024) and tulu-3-sft-personas-math (Lambert et al., 2025; Allen Institute for AI, 2025), respectively. The default chat template is applied to all SFT datasets and </think> tags are explicitly closed to disable reasoning in hybrid reasoning models. Table 1: Comparison of SMoE models included in our study. | Model | Routed Experts | Shared Experts | Top-K | Sparsity | Parameters (1e9) | Active Params. (1e9) | First layer dense | | --- | --- | --- | --- | --- | --- | --- | --- | | ERNIE-4.5-21B-A3B-PT | 64 | 2 | 6 | 87.88% | 21.9 | 3 | Yes | | Qwen3-30B-A3B | 128 | 0 | 8 | 93.75% | 30.5 | 3 | No | | Mixtral-8x7B-Instruct-v0.1 | 8 | 0 | 2 | 75.00% | 46.7 | 13 | No | | GLM-4.5-Air | 128 | 1 | 8 | 93.02% | 106.9 | 12 | Yes | | Llama-4-Scout-17B-16E-Instruct | 16 | 1 | 1 | 88.24% | 107.8 | 17 | No | | Qwen3-Coder-480B-A35B-Instruct-FP8 | 160 | 0 | 8 | 95.00% | 480.2 | 35 | No | | Kimi-K2-Instruct-W4A16 (RedHatAI, 2025) | 384 | 1 | 8 | 97.66% | 1026.4 | 32 | Yes | Evaluation. Compressed SMoE models are evaluated on a suite of benchmarks including MC question answering, code generation, mathematical reasoning, creative writing, and tool calling. See Appendix ˜ C for details. We implement HC-SMoE and M-SMoE as expert merging baselines. Average linkage criterion is used for HC-SMoE. M-SMoE does not include low-rank compression from the complete MC-SMoE method. Pruning baselines consist of frequency-based pruning and EAN. See Appendix ˜ D for formal definitions. 5.1 Results In Tables ˜ 2 and 2 code generation, creative writing, math reasoning, and MC results are presented for Qwen3-30B and GLM-4.5-Air after calibration with the evol-codealpaca dataset. Table ˜ 3 contains results for large-scale SMoE pruned models on code generation, tool calling, and MC benchmarks. See Table ˜ A4 and Table ˜ A5 for detailed MC and code generation results, respectively. Figure ˜ A5 depicts coding generation and MC accuracy verses model parameters. See Appendix ˜ E for additional results. Zero-shot MC question answering. Both merging and pruning are capable of producing accurate compressed SMoE models for MC question answering. HC-SMoE and REAP have a mean decrease in accuracy of approximately 4% and 13% for compression ratios of 25% and 50%, respectively, excluding large-scale SMoEs. REAP achieves first or second rank among all methods, models and compression ratios, suggesting strong consistency regardless of specific model architecture. When calibrated on c4, we find slightly improved accuracies for all compression methods with similar rankings as noted above, see Table ˜ A6. Generative benchmarks. Compared to MC, generative benchmarks are more representative of real-world use cases of LLMs. In this setting, pruning emerges as the clearly superior compression method on the generative task benchmarks. Excluding large-scale SMoEs, REAP achieves a mean decrease in accuracy of 2.8% and 8.0% at 25% and 50% compression ratios, respectively, on coding. In comparison, both HC-SMoE and M-SMoE produce mean decreases in accuracy >5% at 25% compression and >20% at 50% compression. Notably, REAP maintains significantly higher accuracy at 50% compression than other pruning methods. On creative writing, REAP and EAN are near-lossless at 25% compression with REAP offering improved quality at 50% compression. Merging methods are less consistent across various model architectures and compression ratios. For example, M-SMoE is the best method for Qwen3-30B at 50% compression, but the worst on GLM-4.5-Air. REAP attains the best mathematical reasoning results with a remarkable mean decrease in accuracy of just 1.1% at 50% compression. HC-SMoE and M-SMoE offer high accuracy at 25% compression but are significantly less accurate than pruning at 50% compression. Table 2: MC and generative benchmark results for Qwen3-30B and GLM-4.5-Air. | | Coding | Creative Writing | Math | MC | | | | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | Model | Compression | Technique | Method | Eval+ | LiveCode | Code Avg | WildBench | GSM8K | MATH-500 | Math Avg | MC Avg | | Qwen3-30B-A3B | Baseline | 0.859 | 0.302 | 0.581 | 0.811 | 0.903 | 0.872 | 0.887 | 0.721 | | | | 25% | Merging | M-SMoE | 0.822 | 0.293 | 0.558 | 0.805 | 0.901 | 0.872 | 0.886 | 0.558 | | | HC-SMoE | 0.800 | 0.258 | 0.529 | 0.497 | 0.864 | 0.834 | 0.849 | 0.674 | | | | | Pruning | Frequency | 0.849 | 0.302 | 0.576 | 0.807 | 0.905 | 0.864 | 0.885 | 0.600 | | | | EAN | 0.840 | 0.311 | 0.576 | 0.811 | 0.895 | 0.866 | 0.881 | 0.603 | | | | | REAP | 0.843 | 0.308 | 0.575 | 0.804 | 0.892 | 0.864 | 0.878 | 0.669 | | | | | 50% | Merging | M-SMoE | 0.621 | 0.205 | 0.413 | 0.725 | 0.824 | 0.838 | 0.831 | 0.451 | | | HC-SMoE | 0.574 | 0.185 | 0.379 | 0.008 | 0.760 | 0.696 | 0.728 | 0.542 | | | | | Pruning | Frequency | 0.704 | 0.236 | 0.470 | 0.677 | 0.882 | 0.860 | 0.871 | 0.483 | | | | EAN | 0.798 | 0.306 | 0.552 | 0.702 | 0.886 | 0.842 | 0.864 | 0.493 | | | | | REAP | 0.821 | 0.293 | 0.557 | 0.718 | 0.878 | 0.872 | 0.875 | 0.518 | | | | | GLM-4.5-Air | Baseline | 0.820 | 0.374 | 0.597 | 0.839 | 0.846 | 0.918 | 0.882 | 0.747 | | | | 25% | Merging | M-SMoE | 0.781 | 0.330 | 0.555 | 0.781 | 0.848 | 0.880 | 0.864 | 0.596 | | | HC-SMoE | 0.793 | 0.363 | 0.578 | 0.788 | 0.842 | 0.908 | 0.875 | 0.704 | | | | | Pruning | Frequency | 0.805 | 0.341 | 0.573 | 0.793 | 0.832 | 0.908 | 0.870 | 0.648 | | | | EAN | 0.821 | 0.374 | 0.597 | 0.824 | 0.839 | 0.908 | 0.874 | 0.637 | | | | | REAP | 0.794 | 0.390 | 0.592 | 0.831 | 0.835 | 0.926 | 0.880 | 0.678 | | | | | 50% | Merging | M-SMoE | 0.493 | 0.099 | 0.296 | 0.391 | 0.465 | 0.466 | 0.465 | 0.444 | | | HC-SMoE | 0.662 | 0.220 | 0.441 | 0.593 | 0.667 | 0.732 | 0.700 | 0.564 | | | | | Pruning | Frequency | 0.546 | 0.104 | 0.325 | 0.604 | 0.615 | 0.612 | 0.613 | 0.521 | | | | EAN | 0.773 | 0.253 | 0.513 | 0.702 | 0.781 | 0.838 | 0.809 | 0.511 | | | | | REAP | 0.755 | 0.352 | 0.553 | 0.754 | 0.820 | 0.926 | 0.873 | 0.559 | | | | Table 3: Large-scale pruned SMoEs on agentic, non-agentic coding, tool-use tasks, and MC benchmarks. | | Non-Agentic Coding | Agentic Coding | Tool-Use (BFCLv3) | MC | | | | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | Model | Compression | Method | Eval+ | LiveCode | Code Avg | SWE-Bench-Verified | Non-Live | Live | Multi-Turn | Overall | MC Avg | | Qwen3-Coder- 480B-A35B- Instruct-FP8 | Baseline | 0.889 | 0.431 | 0.660 | 0.540 | 0.866 | 0.825 | 0.380 | 0.690 | 0.750 | | | 25% | Frequency | 0.792 | 0.296 | 0.544 | 0.378 | 0.844 | 0.763 | 0.355 | 0.654 | 0.606 | | | EAN | 0.876 | 0.419 | 0.647 | 0.534 | 0.831 | 0.813 | 0.384 | 0.676 | 0.702 | | | | REAP | 0.884 | 0.416 | 0.650 | 0.540 | 0.878 | 0.823 | 0.392 | 0.698 | 0.748 | | | | 50% | Frequency | 0.011 | 0.012 | 0.011 | 0.000 | 0.200 | 0.392 | 0.000 | 0.197 | 0.506 | | | EAN | 0.831 | 0.382 | 0.607 | 0.536 | 0.822 | 0.774 | 0.383 | 0.659 | 0.591 | | | | REAP | 0.873 | 0.415 | 0.644 | 0.522 | 0.849 | 0.801 | 0.371 | 0.674 | 0.692 | | | | Kimi-K2- Instruct- W4A16 | Baseline | 0.883 | 0.434 | 0.659 | 0.554 | 0.840 | 0.802 | 0.355 | 0.666 | 0.780 | | | 25% | Frequency | 0.524 | 0.082 | 0.303 | 0.000 | 0.644 | 0.603 | 0.045 | 0.431 | 0.604 | | | EAN | 0.831 | 0.379 | 0.605 | 0.562 | 0.819 | 0.802 | 0.335 | 0.652 | 0.703 | | | | REAP | 0.889 | 0.440 | 0.664 | 0.580 | 0.842 | 0.801 | 0.263 | 0.635 | 0.773 | | | | 50% | Frequency | 0.124 | 0.000 | 0.062 | 0.000 | 0.255 | 0.397 | 0.003 | 0.218 | 0.439 | | | EAN | 0.772 | 0.253 | 0.513 | 0.576 | 0.778 | 0.767 | 0.173 | 0.573 | 0.587 | | | | REAP | 0.863 | 0.429 | 0.646 | 0.576 | 0.785 | 0.743 | 0.164 | 0.564 | 0.643 | | | <details> <summary>2510.13999v1/x6.png Details</summary>  ### Visual Description # Technical Document Extraction: Bar Chart Analysis ## Chart Overview The image contains a comparative bar chart analyzing **mean accuracy (%)** across four tasks (**Coding, Math, Creative Writing, MC**) for two language models: **GLM-4.5-Air** and **Qwen3-30B-A3B**. The chart includes **pruning methods** (REAP, EAN, Frequency) and **merging methods** (HC-SMoE, M-SMoE), with **compression ratios** (0%, 50%, 25%) indicated by dashed lines. --- ## Key Components ### Legend - **Location**: Right side of the chart. - **Compression Ratios**: - 0%: Solid gray line. - 50%: Dark blue line. - 25%: Light gray line. - **Pruning Methods**: - REAP (ours): Blue. - EAN: Red. - Frequency: Green. - **Merging Methods**: - HC-SMoE: Yellow. - M-SMoE: Light blue. ### Axes - **X-axis**: Tasks (Coding, Math, Creative Writing, MC). - **Y-axis**: Mean Accuracy (%) ranging from 0% to 90%. --- ## Data Extraction ### GLM-4.5-Air | Task | REAP (ours) | EAN | Frequency | HC-SMoE | M-SMoE | |--------------------|-------------|-------|-----------|---------|--------| | **Coding** | 58% | 52% | 32% | 45% | 30% | | **Math** | 88% | 82% | 61% | 70% | 58% | | **Creative Writing** | 82% | 79% | 60% | 78% | 40% | | **MC** | 72% | 65% | 53% | 68% | 45% | ### Qwen3-30B-A3B | Task | REAP (ours) | EAN | Frequency | HC-SMoE | M-SMoE | |--------------------|-------------|-------|-----------|---------|--------| | **Coding** | 56% | 54% | 48% | 52% | 42% | | **Math** | 89% | 87% | 85% | 83% | 81% | | **Creative Writing** | 81% | 77% | 75% | 73% | 70% | | **MC** | 70% | 63% | 58% | 65% | 50% | --- ## Trends and Observations 1. **REAP (ours)** consistently achieves the highest accuracy across all tasks and models. 2. **Math** task shows the highest performance for both models, with Qwen3-30B-A3B reaching **89%** (REAP). 3. **Coding** task has the lowest accuracy for both models (GLM: 58%, Qwen3: 56%). 4. **Compression Ratios**: - 0% (solid gray) represents baseline performance. - 50% (dark blue) and 25% (light gray) indicate reduced accuracy compared to baseline, but exact values are not explicitly labeled in the chart. 5. **Merging Methods** (HC-SMoE, M-SMoE) generally underperform compared to pruning methods. --- ## Spatial Grounding - **Legend Position**: Right-aligned, outside the main chart area. - **Bar Colors**: Match legend labels exactly (e.g., REAP = blue, EAN = red). --- ## Component Isolation ### Header - Title: Not explicitly labeled, but inferred from context as a comparison of pruning/merging methods. ### Main Chart - **GLM-4.5-Air** (Left): - Math task dominates with **88%** (REAP). - Coding task is the weakest (**58%**). - **Qwen3-30B-A3B** (Right): - Math task peaks at **89%** (REAP). - Creative Writing shows strong performance (**81%**). ### Footer - No explicit footer text; compression ratios are integrated into the legend. --- ## Final Notes - All data points align with legend color assignments. - Dashed lines (compression ratios) suggest performance degradation but lack explicit numerical labels. - REAP (ours) outperforms all other methods in both models. </details> Figure 2: GLM-4.5-Air and Qwen3-30B accuracy vs. task type. REAP offers significant improvements compared to other methods at 50% compression. Note the significant performance drop for merging methods on generative tasks (Coding, Math, Creative Writing) compared to their relative strength on MC. Expert pruning at scale. To asses whether pruning remains viable at scale, we prune Qwen3-Coder-480B and Kimi-K2-Instruct. On MC questions, REAP outperforms other pruning methods. On non-agentic coding tasks, REAP achieves near-lossless accuracy with a 0.20% and 1.4% mean decrease in accuracy compared to baseline at 25% and 50%, respectively, outperforming EAN and frequency-based pruning, particularly at 50% compression. On the challenging SWE-Bench task, both REAP and EAN maintain high accuracy at 25% and 50% compression, with some scores slightly exceeding the baseline. On tool use, EAN and REAP are comparable, with REAP slightly outperforming at 50% compression with a mean decrease in accuracy of 5.9% versus 6.2% for EAN. Frequency-based pruning suffers from a sharp degradation in quality at 50% compression, highlighting the importance of pruning saliency criteria which consider expert activations. Scaling the pruning methods is relatively trivial. Unlike HC-SMoE, calibration for pruning does not require recording activations from every expert for every token, facilitating efficient calibration. Further, pruning can be easily applied to quantized models without any additional steps required to reconcile block scales or re-quantize following compression. <details> <summary>2510.13999v1/x7.png Details</summary>  ### Visual Description # Technical Document Extraction: N-gram Diversity Analysis ## Chart Description The image presents a comparative box plot analysis of **N-gram diversity** across varying **N-gram sizes** (2, 3, 4) for four computational methods: Baseline, REAP, M-SMoE, and HC-SMoE. The y-axis represents N-gram diversity (0.2–1.0), while the x-axis categorizes data by N-gram size. --- ## Key Components ### Labels & Axis Titles - **Y-axis**: "N-gram diversity" (scale: 0.2–1.0) - **X-axis**: "N-gram size" (categories: 2, 3, 4) - **Legend**: - Gray: Baseline - Dark Blue: REAP - Light Blue: M-SMoE - Gold: HC-SMoE ### Box Plot Structure Each box plot includes: - **Box**: Interquartile range (IQR) of N-gram diversity - **Median line**: Central tendency within the IQR - **Whiskers**: Range excluding outliers - **Outliers**: Represented as open circles --- ## Data Trends ### N-gram Size = 2 - **Baseline**: Median ~0.85 (IQR: ~0.8–0.9) - **REAP**: Median ~0.82 (IQR: ~0.75–0.85) - **M-SMoE**: Median ~0.8 (IQR: ~0.75–0.85) - **HC-SMoE**: Median ~0.75 (IQR: ~0.7–0.8) ### N-gram Size = 3 - **Baseline**: Median ~0.9 (IQR: ~0.85–0.95) - **REAP**: Median ~0.88 (IQR: ~0.83–0.92) - **M-SMoE**: Median ~0.85 (IQR: ~0.8–0.9) - **HC-SMoE**: Median ~0.8 (IQR: ~0.75–0.85) ### N-gram Size = 4 - **Baseline**: Median ~0.92 (IQR: ~0.88–0.95) - **REAP**: Median ~0.9 (IQR: ~0.85–0.93) - **M-SMoE**: Median ~0.88 (IQR: ~0.83–0.92) - **HC-SMoE**: Median ~0.85 (IQR: ~0.8–0.88) --- ## Observations 1. **General Trend**: N-gram diversity decreases as N-gram size increases across all methods. 2. **Method Performance**: - **Baseline** consistently achieves the highest median diversity. - **HC-SMoE** exhibits the lowest median diversity but comparable spread to other methods. - **REAP** and **M-SMoE** show intermediate performance, with REAP slightly outperforming M-SMoE in larger N-gram sizes. 3. **Outliers**: Scattered outliers (open circles) indicate variability in individual data points, particularly for N=2 and N=4. --- ## Transcribed Text - **Legend Labels**: - Baseline - REAP - M-SMoE - HC-SMoE - **Axis Markers**: - Y-axis ticks: 0.2, 0.4, 0.6, 0.8, 1.0 - X-axis ticks: 2, 3, 4 --- ## Conclusion The chart demonstrates that larger N-gram sizes correlate with reduced diversity, with the Baseline method maintaining the highest performance. HC-SMoE underperforms relative to other methods, suggesting potential limitations in its N-gram handling strategy. </details> (a) N-Gram diversity <details> <summary>2510.13999v1/x8.png Details</summary>  ### Visual Description # Technical Document Extraction: Cross Perplexity Analysis of Generator Models ## Figure Description This image presents a comparative analysis of **cross perplexity** across three generator models using violin plots. The data is visualized on a logarithmic scale (base 10) to emphasize distributional differences. --- ### **Key Components** 1. **Axes** - **Y-axis**: Labeled "Cross perplexity" with logarithmic scaling (10⁰ to 10¹). Dashed horizontal lines mark 10⁰ and 10¹. - **X-axis**: Categorizes generator models: - REAP (dark blue) - M-SMoE (teal) - HC-SMoE (olive) 2. **Violin Plot Structure** - **Shapes**: Each violin represents the probability density of cross perplexity values for a model. - **Width**: Indicates density of data points at specific perplexity levels. - **Tails**: Extend to show minimum/maximum values (e.g., HC-SMoE has the longest upper tail). - **Black Lines**: Represent the **interquartile range (IQR)**. - **White Lines**: Denote the **median** value within the IQR. --- ### **Key Trends and Data Points** 1. **Model Performance** - **HC-SMoE**: - Highest median perplexity (~10⁰.⁵). - Widest IQR (indicating greater variability in results). - Longest upper tail (outliers up to ~10¹). - **M-SMoE**: - Median ~10⁰.⁴. - Moderate IQR and tail spread. - **REAP**: - Lowest median (~10⁰.³). - Narrowest IQR (most consistent performance). - Shortest tails (least extreme values). 2. **Logarithmic Scale Implications** - Differences in medians and spreads are amplified due to the log scale. - HC-SMoE’s performance is notably worse than REAP by an order of magnitude in upper tail values. --- ### **Critical Observations** - **REAP** demonstrates the most stable and lowest perplexity, suggesting superior generalization. - **HC-SMoE** exhibits the highest variability and worst-case performance, despite potential advantages in other metrics. - **M-SMoE** balances performance and variability but underperforms REAP in median perplexity. --- ### **Technical Notes** - No explicit legend is present; model identities are inferred from x-axis labels and color coding. - All violins share identical axis scaling, enabling direct comparison. - The absence of numerical annotations on the violins limits precise quantification of IQR/median values. --- This visualization highlights trade-offs between model complexity (e.g., HC-SMoE’s higher capacity) and performance stability (REAP’s consistency). Further analysis could explore why HC-SMoE exhibits such variability despite its architectural sophistication. </details> (b) Cross perplexity <details> <summary>2510.13999v1/x9.png Details</summary>  ### Visual Description # Technical Document Extraction: Line Chart Analysis ## Chart Type Line chart with shaded confidence intervals. ## Axis Labels - **X-axis**: Token Position (0 to 20, increments of 10) - **Y-axis**: JSD (0.0 to 0.7, increments of 0.1) ## Legend - **REAP**: Dark blue line - **M-SMoE**: Light blue line - **HC-SMoE**: Gold line ## Key Trends 1. **Initial Behavior**: - All lines start at (0, 0) and rise sharply in the first 5 token positions. - HC-SMoE (gold) begins highest, followed by M-SMoE (light blue), then REAP (dark blue). 2. **Mid-Range (Token Positions 5–15)**: - Lines diverge further, with HC-SMoE maintaining the highest JSD values. - M-SMoE shows moderate growth, while REAP lags slightly behind. 3. **Final Segment (Token Positions 15–20)**: - All lines plateau near 0.6–0.65 JSD. - HC-SMoE remains the highest, with REAP approaching M-SMoE but not surpassing it. ## Shaded Regions - Gray bands around each line represent confidence intervals or error margins. - HC-SMoE exhibits the widest variability (broadest shaded region), particularly after token position 10. ## Data Points - **Token Position 0**: All lines at 0.0 JSD. - **Token Position 10**: - REAP: ~0.4 - M-SMoE: ~0.55 - HC-SMoE: ~0.5 - **Token Position 20**: - REAP: ~0.6 - M-SMoE: ~0.62 - HC-SMoE: ~0.65 ## Observations - Lines do not intersect; relative order (HC-SMoE > M-SMoE > REAP) is preserved throughout. - JSD values for all models increase monotonically with token position. - HC-SMoE demonstrates the steepest initial growth and highest final JSD. </details> (c) Completion logit JSD <details> <summary>2510.13999v1/x10.png Details</summary>  ### Visual Description # Technical Document Extraction: Chart Analysis ## Chart Components ### Axes - **X-axis (Horizontal):** - Label: `Layer` - Range: `0` to `40` (increments of `8`) - **Y-axis (Vertical):** - Label: `SV Align. ↑ / L2 Distance ↓` - Range: `0.0` to `1.4` ### Legend - **Dist. Type (Distance Type):** - `Singular-vector alignment` (solid line) - `L2 Distance` (dashed line) - **Expert clusters:** - `Base to IFT` (gray dashed line) - `HC-SMoE` (yellow line) - `M-SMoE` (blue line) - `M-SMoE - permuted` (magenta line) ### Key Trends 1. **Base to IFT (gray dashed line):** - Remains relatively stable across all layers. - Slight upward trend observed between layers `0` and `8`. 2. **HC-SMoE (yellow line) and M-SMoE (blue line):** - Overlap significantly throughout the chart. - Both exhibit minor fluctuations but remain near the top of the y-axis range (`~1.4`). 3. **M-SMoE - permuted (magenta line):** - Consistently lower than `HC-SMoE` and `M-SMoE`. - Slightly higher than `Base to IFT` but remains near the bottom of the y-axis range (`~0.2`). 4. **L2 Distance (dashed line):** - Horizontal line at `1.0` across all layers. ### Observations - The `SV Alignment / L2 Distance` ratio for `HC-SMoE` and `M-SMoE` is consistently higher than for `Base to IFT` and `M-SMoE - permuted`. - `M-SMoE - permuted` shows the lowest performance relative to other clusters. - No significant divergence between `HC-SMoE` and `M-SMoE` across layers. ## Diagram Structure - **Lines:** - Solid lines represent `Singular-vector alignment`. - Dashed lines represent `L2 Distance`. - Colored lines correspond to specific expert clusters. - **Shading:** - No explicit shading present; lines are unfilled. ## Data Points - **Layer 0:** - `Base to IFT`: ~0.05 - `HC-SMoE`: ~1.4 - `M-SMoE`: ~1.4 - `M-SMoE - permuted`: ~0.2 - **Layer 40:** - `Base to IFT`: ~0.05 - `HC-SMoE`: ~1.4 - `M-SMoE`: ~1.4 - `M-SMoE - permuted`: ~0.2 ## Notes - The chart compares the performance of different expert clusters (`Base to IFT`, `HC-SMoE`, `M-SMoE`, `M-SMoE - permuted`) across layers. - `L2 Distance` serves as a reference metric, remaining constant at `1.0`. - All lines are plotted against the `Layer` axis, indicating performance trends across model depth. </details> (d) Expert distance Figure 3: (3(a)) & (3(b)) N-Gram diversity and cross-perplexity of compressed Qwen3-30B-A3B models at 50% compression, respectively. (3(c)) JSD of compressed and baseline model logits vs. completion token position for Qwen3-30B-A3B at 50% compression. Initially, all compressed models share close alignment with the baseline model. However, as the completion token position increases the merged models diverge from the baseline more rapidly than the REAP pruned model. (3(d)) The mean relative L2-distance and singular-vector alignment between Qwen3-30B expert weights at 50% compression. Expert merging is more challenging than model merging due to large distances between experts in weight space and low singular-vector alignment. Quantifying merged MoE generation quality. While merged expert SMoEs offer reasonable quality for discriminative tasks such as MC question and answering, they fail to remain competitive on generative tasks. To help explain the performance gap of merged models between discriminative and generative tasks, we perform an analysis of the compressed model outputs and compare with REAP pruned models. We prompt 50% compressed Qwen3-30B models with 100 questions randomly sampled from the evol-codealpaca dataset and record their outputs. In Figure ˜ 3(a), we measure the N-gram diversity and find that the merged models have significantly lower diversity across all N-gram sizes measured. In contrast, the REAP pruned model remains similar to the base model, albeit slightly less diverse. In Figure ˜ 3(b), we measure the perplexity of the text generated by the compressed models with the original baseline model. The text generated by the merged models has both a higher mean and higher variance than the pruned model generations, suggesting that the REAP pruned model outputs are more closely aligned to the original model. The alignment between the baseline and REAP pruned SMoEs is further supported by Figure ˜ 3(c), which plots the JSD of the compressed and baseline logits vs. output token position. The merged model logits diverge from the baseline more rapidly than the pruned model. The challenges of expert merging. Model merging has been widely adopted to facilitate LLM fine-tuning. Why does expert merging miss the mark? In addition to the loss of the router’s input-dependent modulation of experts explored in Section ˜ 3, we argue that the non-local nature of expert merging and high cardinality of expert clusters pose significant unresolved challenges. In Figure ˜ 3(d), we plot the mean relative L2-distance between experts clustered by HC-SMoE or M-SMoE and compare with the distance between expert weights from the pretrained to Instruct Fine-Tuned (IFT) checkpoints. We find that the distance between clustered experts within the same layer greatly exceeds that of experts in the IFT checkpoint after fine-tuning. Ito et al. (2024) found that weight matching permutations improved alignment of parameters’ singular vectors. Following their approach, we decompose expert weights with Singular Value Decomposition (SVD) and plot the singular-vector alignment in Figure ˜ 3(d). Even after applying weight matching permutations, the M-SMoE expert clusters remain far apart both in weight space and singular-vector alignment. The relatively poorly aligned experts highlight the considerable challenge of coherently merging their parameters. When merging works well, it’s more closely related to pruning than one might expect. In Figure ˜ 6(a), we depict the frequency of singleton clusters — clusters containing a single expert — for both HC-SMoE and M-SMoE. A singleton cluster is directly analogous to an expert that remains after pruning. We find that HC-SMoE in particular has a high prevalence of singleton clusters, leaving important experts unadulterated and compressing the rest into a few mega -clusters containing tens of experts. This is particularly true of the high granularity models which contain more experts per layer. We hypothesize that the cardinality of these mega-clusters poses a challenge for existing merging algorithms and test this intuition in Figure ˜ 6(b). Unfortunately, even modest restrictions of the maximum cluster size to 32 — half the number of experts to compress — results in large decreases in model quality on coding tasks. The importance of domain-specific calibration. In Figure ˜ A7, we plot the code generation accuracy of the various compression methods and models when calibrated on either c4 or evol-codealpaca. The difference is stark, c4 calibration results in a collapse in accuracy, with several compressed model instances failing to produce coherent outputs, resulting in 0% accuracy. In Figure ˜ A8, we compare the accuracy of compressed Qwen3-30B models calibrated with either domain-specific data or the combined calibration data across all generative tasks. The domain-specific calibrated models achieve significantly higher accuracy, especially at 50% compression. 6 Discussion Similar to prior work, we find that expert merging performs reasonably well on MC benchmarks. This may be because MC tasks only require a discriminative function that can be approximated by an average expert. In contrast, merging fails to maintain model quality on generative tasks, particularly at 50% compression. Generative tasks require auto-regressive generation, a capability that is lost when the router’s fine-grained control is removed. Compared to expert pruning, merging is less consistent, exhibiting higher variance across models and compression ratios. The outputs of expert merged models are more repetitive and less closely aligned with the base model compared with pruned models. Taken together, these observations are direct evidence of alterations to the functional manifold of the SMoE layers discussed in Section ˜ 3.3 stemming from the loss of the router’s input-dependent control over the experts and subsequent introduction of novel functions due to tying of the merged expert gates. Overall, expert pruned models offer consistently higher accuracy than merged models on generative tasks. REAP is a robust pruning criterion that generalizes across a wide array of SMoE architectures, compression ratios, and generative tasks. By taking into consideration both the router gate-values and expert activation norms, REAP prunes the experts which contribute the least to each layers output on a per-token average, regardless of usage frequency. REAP is scalable, achieving near-lossless compression on coding tasks with Qwen3-Coder-480B and Kimi-K2. The successes of REAP highlights the crucial importance of preserving coordination between the router and experts. Compression methods which impair the router’s ability to independently modulate expert outputs or tie gate-values are less likely to succeed. Finally, this work highlights the importance of comprehensive downstream evaluations and the significant challenges involved with evaluating LLMs. Discriminative metrics such as perplexity and log-likelihood based MC benchmarks are not necessarily good proxies for generative model quality. 7 Conclusion Our analysis of current SMoE expert merging techniques finds that the router’s loss of independent control over experts results in functional subspace collapse. In contrast, expert pruning produces a coordinate subspace of the original layer which maintains the topology of the functional manifold. Based on our findings that the coordination between the router and experts is fundamental, we introduce REAP, a novel expert pruning method which prunes experts that contribute the least to the layer’s output. Empirically, we demonstrate that REAP retains remarkably high accuracy on an wide array of generative tasks across a diverse set of model architectures. We hope that this work inspires further compression techniques for SMoEs and facilitates the deployment of accurate, domain-specific models in resource constrained settings. Acknowledgments We would like to acknowledge the helpful feedback of Mohammed Adnan and Rohan Jain. ML and YI gratefully acknowledge the support of Alberta Innovates (ALLRP-577350-22, ALLRP-222301502), the Natural Sciences and Engineering Research Council of Canada (NSERC) (RGPIN-2022-03120, DGECR-2022-00358), and Defence Research and Development Canada (DGDND-2022-03120). ML and YI are grateful for computational resources made available to us by the Digital Research Alliance of Canada. YI is supported by a Schulich Research Chair. Ethics Statement This work research focused on the algorithmic compression of SMoE models and does not involve the use of human subjects, personally identifiable information, or sensitive data. The datasets used for calibration and evaluation (e.g., c4, evol-codealpaca) are publicly available. Our aim is enable the use of large-scale SMoE models in resource constrained settings. However, we acknowledge that compression techniques such as REAP could potentially facilitate deployment of models for malicious purposes. Further, our compression methods are applied to pre-trained models and any biases related to fairness, discrimination, or representation inherent in the original models may be present in their compressed versions. We make no attempt in this work to mitigate these potential biases. The primary contribution of this paper is technical, and we do not foresee any new, direct ethical concerns arising from our proposed methodology beyond those already associated with the deployment of large language models. Reproducibility Statement We are committed to ensuring the reproducibility of our research. We have open-sourced our code and released select compressed model checkpoints to facilitate further research on compressed SMoEs. REAP is formally described in Section 4. The baseline methods we compare against, including frequency-based pruning, EAN, M-SMoE, and HC-SMoE, are formally defined in Appendix D. Section 5 provides a detailed description of our experimental setup, including the specific models used, the calibration and evaluation datasets, and the implementation details for all compression experiments. Further evaluation details are provided in Appendix C. References - Ainsworth et al. (2023) Samuel Ainsworth, Jonathan Hayase, and Siddhartha Srinivasa. 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GLM-4.5: Agentic, Reasoning, and Coding (ARC) Foundation Models, August 2025. URL http://arxiv.org/abs/2508.06471. arXiv:2508.06471 [cs]. Appendix A Extension to Hierarchical Clustering While Theorem 1 analyses pairwise merging, practical implementations often employ hierarchical clustering to form groups of experts. Consider a cluster $C=\{f_{i_{1}},...,f_{i_{k}}\}$ of $k$ experts merged into a single representative $\tilde{f}_{C}$ . The original contribution of this cluster can be decomposed as: $$ \sum_{j\in C}g_{i_{j}}(x)f_{i_{j}}(x)=\left(\sum_{j\in C}g_{i_{j}}(x)\right)\cdot\underbrace{\sum_{j\in C}w_{j}(x)f_{i_{j}}(x)}_{\text{Dynamic, input-dependent mixture}} \tag{10} $$ where $w_{j}(x)=\frac{g_{i_{j}}(x)}{\sum_{l∈ C}g_{i_{l}}(x)}$ are the within-cluster mixing ratios that sum to 1. After hierarchical merging, the router must apply the summed gate $\sum_{j∈ C}g_{i_{j}}$ to a single, static cluster representative $\tilde{f}_{C}$ , typically computed as a weighted average of the cluster members based on calibration data. This induces an irreducible error: **Theorem 2 (Hierarchical clustering error)** *For a cluster $C$ merged into $\tilde{f}_{C}=\sum_{j∈ C}\alpha_{j}f_{i_{j}}$ with fixed weights $\alpha_{j}≥ 0$ , $\sum_{j}\alpha_{j}=1$ , the minimal $L^{2}$ error is: $$ \min_{\{\alpha_{j}\}}\left\|\sum_{j\in C}g_{i_{j}}f_{i_{j}}-\left(\sum_{j\in C}g_{i_{j}}\right)\tilde{f}_{C}\right\|^{2}=\mathbb{E}\left[\left(\sum_{j\in C}g_{i_{j}}\right)^{2}\right]\cdot\mathrm{Var}_{x}\left[\sum_{j\in C}w_{j}(x)f_{i_{j}}(x)\right] \tag{11} $$ The error grows with both the cluster’s total gate-value and the variance of the dynamic mixture that the cluster must approximate with a static representative.* Implications for cluster formation. The hierarchical error bound reveals a fundamental tension: - Large clusters ( $|C|$ large) aggregate more gate-value $\sum_{j∈ C}g_{i_{j}}$ , amplifying any approximation error - Diverse clusters (high $\|\Delta_{ij}\|$ for $i,j∈ C$ ) increase the variance term, as the static representative must approximate a wider range of functions - Imbalanced clustering (many singletons, few mega-clusters) combines the worst aspects: mega-clusters suffer severe collapse while singletons provide minimal compression Distance metrics like Euclidean distance that consider magnitude can exacerbate these issues by creating clusters based on norm similarity rather than functional role, potentially grouping experts with different specializations but similar scales. The resulting mega-clusters force the router to apply a single control signal to what were previously dozens of independently modulated experts, explaining the catastrophic functional collapse observed empirically in late layers where $\mathrm{Var}[w_{j}(x)]$ is highest. Appendix B Additional empirical evidence for loss of independent control In Figure ˜ 1(a), Qwen3’s layer 0 exemplifies the contraction of the functional output space by merging in early layers. The original 128 experts span from $-0.4$ to $1.0$ along PC1, pruning maintains this full range with 64 experts, while merging contracts the distribution to approximately $[-0.2,0.3]$ , a 5-fold reduction. This contraction is dramatic in late layers, where experts are more specialized. As depicted in Figure ˜ 4(f), the original 15 experts of Llama-4’s layer 47 occupy a vast, multi-modal space spanning PC1 coordinates from $-800$ to $600$ . Pruning preserves this remarkable diversity, with the 8 surviving experts distributed across the same multi-modal regions. However, merging induces a catastrophic collapse to a tiny cluster around coordinates $(200,0)$ , representing nearly two orders of magnitude reduction in functional diversity. This pattern intensifies with the number of experts: Qwen3’s layer 47 (Figure ˜ 1(b)) shows the most severe collapse, with 128 original experts spanning PC1 from $-200$ to $300$ reduced to a minute region after merging, while its 64 pruned experts maintain the original distribution’s full breadth. Manifold geometry preservation Across all models and layers, we observe a fundamental geometric principle: pruning preserves the topology of the functional manifold while merging fundamentally alters it. This distinction is most clearly visible in ERNIE’s representations (Figures 4(a) and 4(b)). In layer 1, the original 64 routed experts plus 2 shared experts form a characteristic curved structure with several outliers representing specialized experts. After pruning, the red points precisely overlay the gray ghost of the original distribution, including the outlier positions, demonstrating that each surviving expert maintains its exact functional role. The merged configuration, however, shows all experts collapsed into a tight cluster at the distribution’s centre, eliminating both the outliers and the manifold’s curvature. The preservation of manifold geometry under pruning reflects the mathematical structure of the operation: the pruned hypothesis class is a coordinate subspace of the original, with the router maintaining independent control over each surviving expert. The geometric collapse under merging visualizes the loss of independent control when gates $g_{i}$ and $g_{j}$ are tied into their sum $(g_{i}+g_{j})$ , the router can no longer independently modulate the two underlying functions, forcing the model to approximate the dynamic mixture $r(x)f_{i}(x)+(1-r(x))f_{j}(x)$ with a static expert $\tilde{f}_{\alpha}$ . Mixtral, with only 8 experts, provides an interesting edge case (Figures 4(c) and 4(d)). Even with fewer experts, the same geometric principles apply. Pruning maintains the convex hull of the original distribution while merging contracts it. The less dramatic collapse compared to models with more experts suggests that with fewer experts, each must remain more general, leading to lower $\|\Delta_{ij}\|^{2}$ (expert gap) and lower $\mathrm{Var}[r(x)]$ (policy variability), both factors in our irreducible error bound. <details> <summary>2510.13999v1/x11.png Details</summary>  ### Visual Description # Technical Document Extraction: Scatter Plot Analysis ## Overview The image contains three scatter plots arranged horizontally, each representing different data groupings. The plots share identical axis labels (PC1 and PC2) and scales, suggesting a consistent dimensionality reduction or feature space representation. --- ### **1. Original Experts** - **Title**: "Original Experts" - **Data Points**: - **Color**: Pink (`#FF69B4`) - **Distribution**: Clustered primarily in the lower-left quadrant (PC1: 0–1, PC2: -1–1). - **Outliers**: Two points at (PC1: ~2.5, PC2: ~1.5) and (PC1: ~-2, PC2: ~-2). - **Axis Labels**: - X-axis: `PC1` (range: -2 to 4) - Y-axis: `PC2` (range: -2 to 1) --- ### **2. Surviving** - **Title**: "Surviving" - **Data Points**: - **Color**: Blue (`#1E90FF`) - **Distribution**: Clustered in the lower-left quadrant (PC1: 0–1, PC2: -1–1), with a secondary cluster near (PC1: 3, PC2: 0.5). - **Outliers**: One point at (PC1: ~-1, PC2: ~-2) and one at (PC1: ~2.5, PC2: ~-1.5). - **Axis Labels**: - X-axis: `PC1` (range: -2 to 4) - Y-axis: `PC2` (range: -2 to 1) --- ### **3. Merged** - **Title**: "Merged" - **Data Points**: - **Color**: Green (`#32CD32`) - **Distribution**: Clustered tightly around the origin (PC1: 0–1, PC2: -0.5–0.5). - **Overlap**: Green points partially overlap with the "Original Experts" cluster. - **Axis Labels**: - X-axis: `PC1` (range: -2 to 4) - Y-axis: `PC2` (range: -2 to 1) --- ### **Legend** - **Categories**: - `Original Experts`: Pink circles (`●`) - `Surviving`: Blue circles (`●`) - `Merged`: Green crosses (`✖`) --- ### **Key Observations** 1. **Dimensionality**: All plots use the same 2D principal component space (PC1 and PC2). 2. **Clustering**: - "Original Experts" and "Merged" show overlapping clusters near the origin. - "Surviving" exhibits a broader distribution with distinct secondary clusters. 3. **Outliers**: - "Original Experts" and "Surviving" contain outliers in the upper-right and lower-left quadrants. - "Merged" has no visible outliers. 4. **Noise**: White dots in "Surviving" and "Merged" plots may represent noise or unclassified data points. --- ### **Technical Notes** - **Gridlines**: Present in all plots for reference. - **Scale Consistency**: Uniform axis ranges across all plots enable direct comparison. - **Data Representation**: Scatter plots use distinct markers (circles vs. crosses) to differentiate categories. </details> (a) ERNIE-4.5-21B Layer 1 <details> <summary>2510.13999v1/x12.png Details</summary>  ### Visual Description # Technical Document Extraction: Scatter Plot Analysis ## Overview The image contains three scatter plots arranged horizontally, each representing a distinct dataset. The plots share identical axis labels (PC1 and PC2) but differ in data points and color coding. Below is a detailed breakdown of each plot's components and trends. --- ### **1. Original Experts** - **Legend Label**: Red points labeled "Original Experts." - **Axis Labels**: - X-axis: PC1 (ranges from -50 to 100) - Y-axis: PC2 (ranges from 0 to 80) - **Data Distribution**: - Primary cluster: Lower-right quadrant (PC1 ≈ 0–10, PC2 ≈ 0–20). - Outliers: - One point at (PC1 ≈ -50, PC2 ≈ 20). - One point at (PC1 ≈ 10, PC2 ≈ 80). - **Key Observations**: - Data is moderately spread, with two distinct outliers in the upper-left and upper-right regions. --- ### **2. Surviving** - **Legend Label**: Blue points labeled "Surviving." - **Axis Labels**: - X-axis: PC1 (ranges from -50 to 100) - Y-axis: PC2 (ranges from 0 to 80) - **Data Distribution**: - Primary cluster: Lower-left quadrant (PC1 ≈ -10–0, PC2 ≈ 0–10). - Outliers: - One point at (PC1 ≈ -50, PC2 ≈ 10). - One point at (PC1 ≈ 10, PC2 ≈ 80). - **Key Observations**: - Data is tightly clustered in the lower-left, with two outliers mirroring the "Original Experts" distribution. --- ### **3. Merged** - **Legend Label**: Green points labeled "Merged." - **Axis Labels**: - X-axis: PC1 (ranges from -50 to 100) - Y-axis: PC2 (ranges from 0 to 80) - **Data Distribution**: - Primary cluster: Lower-center quadrant (PC1 ≈ -5–5, PC2 ≈ 0–5). - Outliers: - One point at (PC1 ≈ -50, PC2 ≈ 10). - One point at (PC1 ≈ 10, PC2 ≈ 80). - **Key Observations**: - Data is highly concentrated in the lower-center, with outliers similar to the other plots. --- ### **Cross-Plot Analysis** - **Legend Consistency**: - Red = Original Experts (confirmed in Plot 1). - Blue = Surviving (confirmed in Plot 2). - Green = Merged (confirmed in Plot 3). - **Outlier Patterns**: - All plots share identical outlier positions at (PC1 ≈ -50, PC2 ≈ 10) and (PC1 ≈ 10, PC2 ≈ 80), suggesting these may represent noise or anomalies. - **Cluster Trends**: - "Original Experts" and "Surviving" clusters are spatially distinct, while "Merged" clusters occupy an intermediate position, indicating potential overlap or integration of features. --- ### **Conclusion** The plots illustrate dimensionality reduction (via PCA) of three datasets. The "Merged" dataset shows reduced variability compared to the original and surviving groups, with tighter clustering. Outliers are consistent across all plots, warranting further investigation into their origin. </details> (b) ERNIE-4.5-21B Layer 27 <details> <summary>2510.13999v1/x13.png Details</summary>  ### Visual Description # Technical Document Extraction: Scatter Plot Analysis ## Chart Overview The image contains three side-by-side scatter plots comparing three datasets across two principal components (PC1 and PC2). Each plot uses distinct markers and colors to differentiate categories. --- ### **Left Plot: Original Experts** - **Legend Label**: "Original Experts" (red dots) - **Axis Labels**: - X-axis: PC1 (ranges from -0.2 to 0.2) - Y-axis: PC2 (ranges from -0.1 to 0.2) - **Data Points**: - Red dots are distributed across the plot with no clear clustering. - Notable positions: - (-0.1, 0.0) - (0.0, 0.0) - (0.1, 0.1) - (0.2, 0.2) - (-0.2, -0.1) --- ### **Middle Plot: Surviving** - **Legend Label**: "Surviving" (blue dots) - **Axis Labels**: - X-axis: PC1 (ranges from -0.2 to 0.2) - Y-axis: PC2 (ranges from -0.1 to 0.2) - **Data Points**: - Blue dots cluster near the origin (0,0) with slight spread. - Notable positions: - (-0.1, -0.1) - (0.0, -0.05) - (0.1, 0.0) - (0.15, 0.05) - (-0.05, 0.1) --- ### **Right Plot: Merged** - **Legend Label**: "Merged" (green crosses) - **Axis Labels**: - X-axis: PC1 (ranges from -0.2 to 0.2) - Y-axis: PC2 (ranges from -0.1 to 0.2) - **Data Points**: - Green crosses are sparsely distributed, with some overlap with other plots. - Notable positions: - (-0.1, 0.0) - (0.0, 0.0) - (0.1, 0.1) - (0.15, 0.05) - (-0.05, -0.05) --- ### **Key Observations** 1. **Dimensionality Reduction**: All plots use PC1 and PC2, suggesting Principal Component Analysis (PCA) was applied to reduce feature dimensions. 2. **Distribution Patterns**: - "Original Experts" (red) show wider dispersion. - "Surviving" (blue) cluster closer to the origin. - "Merged" (green) exhibit intermediate spread with some overlap. 3. **No Explicit Trends**: No clear linear or nonlinear trends are evident in any plot. --- ### **Technical Notes** - **Legend Consistency**: Each plot uses distinct markers (dots vs. crosses) and colors to avoid ambiguity. - **Axis Scaling**: All axes share identical ranges (-0.2 to 0.2 for PC1; -0.1 to 0.2 for PC2), enabling direct comparison. - **Missing Data**: No annotations or numerical labels are present on individual data points. --- This extraction captures all textual and structural elements of the chart. The absence of numerical annotations or explicit trends suggests the focus is on visual comparison of distributions across datasets. </details> (c) Mixtral-8x7B Layer 0 <details> <summary>2510.13999v1/x14.png Details</summary>  ### Visual Description # Technical Document Extraction: Scatter Plot Analysis ## Overview The image contains three scatter plots arranged horizontally, each representing different data categories. The plots share identical axis labels (PC1 and PC2) and ranges (-100 to 100), but differ in data point distribution and color coding. --- ### **1. Original Experts** - **Legend**: Pink dots labeled "Original Experts" - **Axis Labels**: - X-axis: PC1 (range: -100 to 100) - Y-axis: PC2 (range: -100 to 100) - **Data Distribution**: - Points are scattered across the plot with no clear clustering. - Notable coordinates: - (-100, 20), (0, 20), (50, 20), (100, 20) - (-50, -40), (0, -60) - **Trend**: Dispersed distribution with points concentrated in the upper half (PC2 > 0). --- ### **2. Surviving** - **Legend**: Blue dots labeled "Surviving" - **Axis Labels**: - X-axis: PC1 (range: -100 to 100) - Y-axis: PC2 (range: -100 to 100) - **Data Distribution**: - Points cluster in the positive PC1 and PC2 quadrant. - Notable coordinates: - (-50, -40), (0, 0), (50, 20), (100, 40) - **Trend**: Concentrated in the upper-right quadrant (PC1 > 0, PC2 > 0), suggesting a survival bias toward higher PC1/PC2 values. --- ### **3. Merged** - **Legend**: Green crosses labeled "Merged" - **Axis Labels**: - X-axis: PC1 (range: -100 to 100) - Y-axis: PC2 (range: -100 to 100) - **Data Distribution**: - Fewer points compared to the other plots, indicating data reduction post-merging. - Notable coordinates: - (-50, -40), (0, 0), (50, 20), (100, 40) - **Trend**: Sparse distribution with points aligned along a diagonal from lower-left to upper-right (PC1 ≈ PC2). --- ### **Legend Spatial Grounding** - **Original Experts**: Top-left of the first plot (pink). - **Surviving**: Top-left of the second plot (blue). - **Merged**: Top-left of the third plot (green). --- ### **Key Observations** 1. **Data Reduction**: The "Merged" plot contains significantly fewer points than the original datasets, suggesting a filtering or consolidation process. 2. **Survival Bias**: The "Surviving" category exhibits a clear preference for higher PC1 and PC2 values compared to "Original Experts." 3. **Dimensionality**: All plots use the same principal components (PC1 and PC2), indicating consistent feature extraction across categories. --- ### **Data Table Reconstruction** | Category | Color | Data Points (PC1, PC2) | Count | |-------------------|-------|--------------------------------------------|-------| | Original Experts | Pink | (-100, 20), (0, 20), (50, 20), (100, 20), (-50, -40), (0, -60) | 6 | | Surviving | Blue | (-50, -40), (0, 0), (50, 20), (100, 40) | 4 | | Merged | Green | (-50, -40), (0, 0), (50, 20), (100, 40) | 4 | --- ### **Conclusion** The plots illustrate a dimensionality reduction process where "Original Experts" are dispersed, "Surviving" data points cluster in high-PC1/PC2 regions, and "Merged" data shows reduced dimensionality with aligned points. The consistent axis ranges and legend placement ensure comparability across categories. </details> (d) Mixtral-8x7B Layer 31 <details> <summary>2510.13999v1/x15.png Details</summary>  ### Visual Description # Technical Document Extraction: Scatter Plot Analysis ## Overview The image contains three scatter plots comparing three categories: **Original Experts**, **Surviving**, and **Merged**. Each plot uses Principal Component 1 (PC1) and Principal Component 2 (PC2) as axes, with values ranging from **-0.05 to 0.05** for both axes. Points are color-coded and symbol-coded to distinguish categories. --- ## Plot 1: Original Experts - **Title**: Original Experts - **Axes**: - X-axis: PC1 (range: -0.05 to 0.05) - Y-axis: PC2 (range: -0.01 to 0.01) - **Data Points**: - **Color**: Pink (`#FF69B4`) - **Symbol**: Circular markers (`●`) - **Distribution**: - Points are scattered across the plot, with a slight concentration near the center (PC1 ≈ 0, PC2 ≈ 0). - No clear clustering or linear trends observed. --- ## Plot 2: Surviving - **Title**: Surviving - **Axes**: - X-axis: PC1 (range: -0.05 to 0.05) - Y-axis: PC2 (range: -0.01 to 0.01) - **Data Points**: - **Color**: Blue (`#1E90FF`) - **Symbol**: Circular markers (`●`) - **Distribution**: - Points are tightly clustered near the center (PC1 ≈ 0, PC2 ≈ 0). - Reduced spread compared to "Original Experts," suggesting lower variability. --- ## Plot 3: Merged - **Title**: Merged - **Axes**: - X-axis: PC1 (range: -0.05 to 0.05) - Y-axis: PC2 (range: -0.01 to 0.01) - **Data Points**: - **Color**: Green (`#32CD32`) - **Symbol**: Cross markers (`✖️`) - **Distribution**: - Points are spread across the plot, with some extending toward the upper-right quadrant (positive PC1 and PC2). - Greater dispersion than "Surviving" but less than "Original Experts." --- ## Legend and Cross-Reference - **Legend Colors**: - Pink (`#FF69B4`): Original Experts - Blue (`#1E90FF`): Surviving - Green (`#32CD32`): Merged - **Symbol Consistency**: - Circular markers (`●`) used for "Original Experts" and "Surviving." - Cross markers (`✖️`) used exclusively for "Merged." --- ## Key Observations 1. **Original Experts** exhibit the widest spread in both PC1 and PC2, indicating higher variability in their principal component values. 2. **Surviving** shows the most concentrated distribution, suggesting reduced dimensionality or filtering of data points. 3. **Merged** retains moderate spread, with a noticeable bias toward positive PC1 and PC2 values. --- ## Notes - No explicit numerical data table is present; all information is derived from scatter plot distributions. - Axis ranges and color/symbol coding are consistent across all plots. - No textual annotations or additional legends are visible in the image. </details> (e) Llama-4 Layer 0 <details> <summary>2510.13999v1/x16.png Details</summary>  ### Visual Description # Technical Document Extraction: PCA Visualization Analysis ## Image Description The image contains three scatter plots arranged horizontally, each representing a distinct dataset or transformation stage. All plots share the same axis labels (**PC1** and **PC2**), indicating principal component analysis (PCA) dimensionality reduction. Points are color-coded to denote categories, with a legend provided for reference. --- ## Key Components & Labels ### Axis Titles - **X-axis**: PC1 (Principal Component 1) - **Y-axis**: PC2 (Principal Component 2) ### Legends - **Red dots**: Original Experts - **Blue dots**: Surviving - **Green crosses**: Merged ### Plot Titles 1. **Original Experts**: Red points distributed across the PC1-PC2 space. 2. **Surviving**: Blue points clustered near the origin (0,0). 3. **Merged**: Green crosses distributed across the PC1-PC2 space, with some overlap with the "Surviving" cluster. --- ## Data Trends & Observations ### 1. Original Experts (Red Dots) - **Distribution**: Scattered across the entire PC1-PC2 range. - **Key Points**: - PC1 range: Approximately -500 to +500. - PC2 range: Approximately -200 to +200. - No clear clustering; points are dispersed. ### 2. Surviving (Blue Dots) - **Distribution**: Concentrated near the origin (0,0). - **Key Points**: - PC1 range: Approximately -100 to +100. - PC2 range: Approximately -50 to +150. - Tight clustering suggests a filtering or selection process (e.g., retaining only high-quality or relevant data points). ### 3. Merged (Green Crosses) - **Distribution**: Overlaps with both "Original Experts" and "Surviving" clusters. - **Key Points**: - PC1 range: Approximately -100 to +500. - PC2 range: Approximately -100 to +200. - Crosses indicate a hybrid dataset, potentially combining "Original Experts" and "Surviving" after transformation. --- ## Cross-Referenced Legend Accuracy - **Red (Original Experts)**: Matches all red dots in the first plot. - **Blue (Surviving)**: Matches all blue dots in the second plot. - **Green (Merged)**: Matches all green crosses in the third plot. --- ## Summary The visualization illustrates a three-stage PCA analysis: 1. **Original Experts**: Full dataset with high variability. 2. **Surviving**: Subset of data points after filtering (clustered near origin). 3. **Merged**: Combined dataset showing transformed relationships between the original and surviving points. All plots use the same PCA axes (PC1 and PC2), enabling direct comparison of data distributions across stages. </details> (f) Llama-4 Layer 47 Figure A4: (4(a), 4(c), 4(e)) Functional subspace (PCA) for early SMoE layers. Pruning (blue) preserves the manifold geometry; merging (green) collapses it toward the centre. (4(b), 4(d), 4(f)) Functional subspace (PCA) for late MoE layers. Appendix C Evaluation details Multiple choice (MC) evaluation. Following Chen et al. (2025), our MC benchmarks include: AI2 Reasoning Challenge (ARC-c & ARC-e) (Clark et al., 2018), BoolQ (Clark et al., 2019), HellaSwag (Zellers et al., 2019), MMLU (Hendrycks et al., 2021a), OpenBookQA (OBQA) (Mihaylov et al., 2018), Recognizing Textual Entailment Challenge (RTE) (Bentivogli et al., 2009), and WinoGrande (WinoG.) (Sakaguchi et al., 2021). We evaluate the models in the zero-shot setting using the standard log-likelihood approach with lm-eval-harness (Gao et al., 2023). We report byte-length normalized accuracies for ARC-c, ARC-e, HellaSwag, and OBQA Reported as the acc_norm field in the EleutherAI evaluation harness outputs. See Gao (2021) for details. . Coding evaluation. For code generation, all models are evaluated on EvalPlus (Liu et al., 2023) and 182 LiveCodeBench (Jain et al., 2025) questions collected between January and April 2025. We extend the original source code for these benchmarks to evaluate our models. We additionally evaluate Kimi-K2-Instruct-W4A16 and Qwen3-Coder-480B on the agentic coding benchmark SWE-Bench (Jimenez et al., 2024) and tool-calling benchmark BFCLv3 (Patil et al., 2025). For BFCLv3, we use the original Gorilla framework for evaluating our models (Patil et al., 2024). For SWE-Bench evaluation, we run our compressed models with the mini-SWE-agent scaffolding (Yang et al., 2024b) and report the score on the SWE-Bench Verified test set (Neil Chowdhury et al., 2024). We use 4,096 and 16,384 as the maximum number of output tokens for evaluating Qwen3-Coder-480B and Kimi-K2-Instruct-W4A16 on SWE-Bench, respectively. The input context length for both models is limited to 65,536. We do not limit the number of turns in mini-SWE-agent flow, but restart the rollout in cases where the model could not generate a valid patch (that is, in the case when the output of the final turn does not contain a diff --git substring). We set the maximum number of restarts to 20, which we found to be sufficient to generate patches for all samples with pruned models, unless the model produces degenerate responses like repeating strings. We use the cloud-based evaluation provided with the sb-cli tool to get the final scores for all evaluated models. For $\tau^{2}$ -bench Barres et al. (2025), we use greedy decoding and 4,096 as the maximum number of output tokens for each LLM call. For user simulation, we use the gpt-4.1-2025-04-14 model; maximum number of steps is 100 and number of trials is set to three for each domain. Following Artificial Analysis (2025), we additionally implement an LLM-based repetition checking step. Every 30 steps of the simulation, a model (in our case, gpt-4.1-mini-2025-04-14) is given the past 30 episodes of the conversation trajectory with a repetition checking prompt to determine whether the agent is stuck in the loop or making meaningful progress. This allows early task termination if the agent is stuck. We use the same decoding parameters for the repetition model as for the user and assistant models. Math and creative writing evaluation. Mathematical reasoning is assessed on GSM8K (Cobbe et al., 2021) and MATH-500 (Hendrycks et al., 2021b; Lightman et al., 2023) benchmarks using the evalscope (ModelScope Team, 2024) framework. To assess creative writing, we use 146 creative writing prompts sampled from WildBench (Lin et al., 2024) with GPT-4o used as the judge to evaluate the model responses. We report normalized scores using the WildBench rubric. Generation configuration. For models with $≤$ 110B parameters, we use greedy sampling (i.e, temperature = 0.0) to evaluate code generation and math reasoning. For creative writing we use the default temperature, top-P, and top-K settings for each respective model. The maximum number of output tokens is extended to 16,384 for all generative tasks to account for the verbosity of some models. For hybrid reasoning models such as Qwen3-30B-A3B, we disable reasoning on all tasks by setting enable $\_$ thinking=False in the chat template. For larger models with $≥$ 110B parameters, we use greedy sampling for EvalPlus, SWE-Bench, and BFCLv3. On LiveCodeBench, Qwen3-Coder-480B and Kimi-K2 are evaluated with default sampling parameters and greedy sampling, respectively. We report the mean and standard deviation for Qwen3-Coder-480B on LiveCodeBench over five random seeds. We use a repetition penalty of 1.05 for all large model evaluations. For EvalPlus we use 768 as the maximum number of output tokens and 16,384 for LiveCodeBench. For BFCLv3 we set the maximum number of output tokens to 4,096. Model details. The Kimi-K2-Instruct-W4A16 model used throughout this study is an INT4 weight-quantized version of Kimi-K2-Instruct released by RedHatAI (2025). Appendix D Baseline methods The following formally describes the baselines compression methods we consider. Notation. Let $\mathcal{X}_{cal}$ be a calibration dataset. Consider a SMoE model with $n$ layers, $L_{n}$ , $K$ experts per layer $f_{1},...,f_{K}$ , each a function $f_{k}:\mathbb{R}^{d}→\mathbb{R}^{d}$ , and a router producing non-negative gates $\mathbf{g}(x)=(g_{1}(x),...,g_{K}(x))∈\Delta^{K-1}$ . The output of layer $L_{n}$ is $$ h_{n}=\sum_{i}^{K}g_{i}(x)f_{i}(x). $$ The expert usage frequency, $\nu_{i}$ , for expert $f_{i}$ is the number of tokens in $\mathcal{X}_{cal}$ for which $f_{i}$ is activated $$ \nu_{i}=|\mathcal{X}_{i}|, $$ where $\mathcal{X}_{i}=\{x∈\mathcal{X}_{cal}\mid i∈\text{TopK}(\mathbf{g}(x))\}$ . Given saliency scores, $\mathbf{S}∈\mathbb{R}^{K}$ , pruning removes experts with the minimum saliency score. For merging, we first cluster experts based on their pairwise distances, $\mathbf{D}∈\mathbb{R}^{K× K}$ , and then merge the parameters of experts contained within each cluster. Frequency-based pruning. The frequency-based pruning saliency criterion prunes experts with the lowest usage frequency across the calibration dataset. The saliency of $f_{i}$ is simply $S_{i}=\nu_{i}$ . EAN pruning. EAN pruning introduced by Jaiswal et al. (2025) accumulates the activation norm of each expert across tokens for which the expert is activated. The saliency of $f_{i}$ is $$ S_{i}=\sum_{x\in\mathcal{X}_{i}}\|f_{i}(x)\|_{2}. \tag{12} $$ M-SMoE merging. Proposed by Li et al. (2023), M-SMoE first uses weight-matching (Ainsworth et al., 2023) to find a permutation matrix $\mathbf{P_{j}}$ which aligns expert $f_{j}$ to expert $f_{i}$ . In the models we study, each expert is a two-layer feed-forward SwiGLU block (Shazeer, 2020) with up, gate, and down projections: $f_{j}=\{W_{up}^{(j)},W_{gate}^{(j)},W_{down}^{(j)}\}$ . The permutation matrix is applied to the intermediate dimension of the experts such that the expert outputs are invariant to the transformation | | $\displaystyle W^{\prime(j)}_{up}=W^{(j)}_{up}\mathbf{P}_{j},$ | $\displaystyle W^{\prime(j)}_{gate}=W^{(j)}_{gate}\mathbf{P}_{j},$ | $\displaystyle W^{\prime(j)}_{down}=\mathbf{P}_{j}^{T}W^{(j)}_{down}.$ | | | --- | --- | --- | --- | --- | The permuted expert is defined as $\tilde{f}_{j}=\{W^{\prime(j)}_{up},W^{\prime(j)}_{gate},W^{\prime(j)}_{down}\}$ . To initialize the expert clusters, M-SMoE identifies the set of $m$ dominant experts $\mathbb{F}_{dom}$ , as the experts across all layers with the highest usage frequency $\nu$ . The pairwise expert distance is based on the cosine distance of the router gate-values measured on the calibration dataset $$ D_{i,j}=\frac{1}{|\mathcal{X}_{cal}|}\sum_{x\in\mathcal{X}_{cal}}1-\frac{g_{i}(x)\cdot g_{j}(x)}{\|g_{i}(x)\|\|g_{j}(x)\|}. \tag{13} $$ Non-dominant expert $j$ is clustered by selecting the dominant expert with the smallest pairwise distance $$ i^{*}=\operatorname*{arg\,min}_{i\in\mathbb{F}_{dom}}D_{i,j}. $$ The merged expert $f_{\alpha}$ is created by calculating the frequency-weighted average of the permuted parameters, $W^{\prime}$ , of all experts in the cluster $\mathbb{C}_{\alpha}$ $$ \tilde{W}_{a}=\frac{\sum_{i\in\mathbb{C}_{\alpha}}\nu_{i}W^{\prime}_{i}}{\sum_{i\in\mathbb{C}_{\alpha}\nu_{i}}}. \tag{14} $$ HC-SMoE merging. Chen et al. (2025) clusters experts based on their representative vectors, $A_{i}$ , defined as the average activation across every token in the calibration dataset $$ A_{i}:=\mathbb{E}_{x\sim\mathcal{X}_{cal}}[f_{i}(x)]=\frac{1}{|\mathcal{X}_{cal}|}\sum_{x\in\mathcal{X}_{cal}}f_{i}(x). $$ The expert pairwise distance is defined as the cosine distance between representative vectors $$ D_{i,j}=1-\frac{A_{i}\cdot A_{j}}{\|A_{i}\|\|A_{j}\|}. \tag{15} $$ Clusters are formed using hierarchical agglomerative clustering with average linkage criterion. We start by initializing each expert as a singleton cluster. At every iteration, the closest pair of clusters, $\mathbb{C}_{i}^{*},\mathbb{C}_{j}^{*}$ are joined and the pairwise distances updated as the average of the constituents | | $\displaystyle i^{*},j^{*}=\operatorname*{arg\,min}_{i,j}D_{i,j},$ | $\displaystyle\mathbb{C}_{\alpha}=\mathbb{C}_{i^{*}}\cup\mathbb{C}_{j^{*}},$ | $\displaystyle D_{a,k}=\frac{\sum_{i∈\mathbb{C}_{\alpha}}D_{i,k}}{|\mathbb{C}_{\alpha}|}.$ | | | --- | --- | --- | --- | --- | The clusters are merged with equation 14. Appendix E Additional results Table ˜ A4 shows the full suite of MC question answering benchmarks and the average result across all models and methods. Table ˜ A5 tabulates code generation accuracy of compressed SMoE models calibrated on evol-codealpaca. Eval+ is the average of MBPP, MBPP+, HumanEval (HE), HE+. The Code Avg column is the average of Eval+ and LiveCodeBench (LiveCode). Table ˜ A6 summarizes the accuracy of the various compression methods studied when calibrated with the c4 dataset on coding and MC benchmarks. Notably, while the MC performance is generally slightly higher than models calibrated on evol-codealpaca, the resulting code generation quality is abysmal, with most models failing to generate coherent output. Table A4: Detailed benchmark results for multiple-choice QA tasks. | Model | Compression | Technique | Method | ARC-c | ARC-e | BoolQ | Hellaswag | MMLU | OBQA | RTE | WinoG. | MC Avg | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | ERNIE-4.5-21B- A3B-PT | Baseline | 0.564 | 0.782 | 0.873 | 0.813 | 0.737 | 0.462 | 0.812 | 0.724 | 0.721 | | | | 25% | Merging | M-SMoE | 0.434 $±$ 0.006 | 0.652 $±$ 0.008 | 0.846 $±$ 0.001 | 0.597 $±$ 0.002 | 0.591 $±$ 0.001 | 0.350 $±$ 0.006 | 0.819 $±$ 0.010 | 0.655 $±$ 0.003 | 0.618 $±$ 0.002 | | | HC-SMoE | 0.506 $±$ 0.000 | 0.717 $±$ 0.001 | 0.849 $±$ 0.001 | 0.714 $±$ 0.001 | 0.652 $±$ 0.002 | 0.371 $±$ 0.002 | 0.799 $±$ 0.002 | 0.674 $±$ 0.004 | 0.660 $±$ 0.001 | | | | | Pruning | Frequency | 0.486 $±$ 0.004 | 0.711 $±$ 0.000 | 0.852 $±$ 0.004 | 0.675 $±$ 0.003 | 0.628 $±$ 0.003 | 0.373 $±$ 0.003 | 0.780 $±$ 0.006 | 0.676 $±$ 0.005 | 0.648 $±$ 0.001 | | | | EAN | 0.498 $±$ 0.005 | 0.713 $±$ 0.002 | 0.863 $±$ 0.002 | 0.717 $±$ 0.004 | 0.625 $±$ 0.001 | 0.405 $±$ 0.011 | 0.811 $±$ 0.009 | 0.702 $±$ 0.005 | 0.667 $±$ 0.000 | | | | | REAP | 0.527 $±$ 0.004 | 0.759 $±$ 0.002 | 0.857 $±$ 0.003 | 0.717 $±$ 0.003 | 0.644 $±$ 0.001 | 0.409 $±$ 0.009 | 0.756 $±$ 0.008 | 0.690 $±$ 0.001 | 0.670 $±$ 0.002 | | | | | 50% | Merging | M-SMoE | 0.294 $±$ 0.033 | 0.452 $±$ 0.040 | 0.764 $±$ 0.010 | 0.341 $±$ 0.011 | 0.385 $±$ 0.001 | 0.270 $±$ 0.004 | 0.687 $±$ 0.017 | 0.529 $±$ 0.010 | 0.465 $±$ 0.012 | | | HC-SMoE | 0.411 $±$ 0.003 | 0.641 $±$ 0.002 | 0.822 $±$ 0.001 | 0.523 $±$ 0.001 | 0.495 $±$ 0.002 | 0.330 $±$ 0.005 | 0.742 $±$ 0.011 | 0.587 $±$ 0.009 | 0.569 $±$ 0.001 | | | | | Pruning | Frequency | 0.400 $±$ 0.002 | 0.584 $±$ 0.006 | 0.830 $±$ 0.001 | 0.522 $±$ 0.003 | 0.506 $±$ 0.006 | 0.303 $±$ 0.004 | 0.758 $±$ 0.004 | 0.625 $±$ 0.004 | 0.566 $±$ 0.002 | | | | EAN | 0.417 $±$ 0.005 | 0.633 $±$ 0.005 | 0.830 $±$ 0.003 | 0.572 $±$ 0.001 | 0.509 $±$ 0.002 | 0.336 $±$ 0.003 | 0.785 $±$ 0.014 | 0.626 $±$ 0.003 | 0.589 $±$ 0.003 | | | | | REAP | 0.417 $±$ 0.009 | 0.626 $±$ 0.007 | 0.803 $±$ 0.006 | 0.556 $±$ 0.003 | 0.505 $±$ 0.003 | 0.325 $±$ 0.006 | 0.775 $±$ 0.014 | 0.623 $±$ 0.008 | 0.579 $±$ 0.002 | | | | | Qwen3-30B-A3B | Baseline | 0.563 | 0.790 | 0.887 | 0.778 | 0.779 | 0.454 | 0.816 | 0.702 | 0.721 | | | | 25% | Merging | M-SMoE | 0.357 $±$ 0.006 | 0.519 $±$ 0.003 | 0.843 $±$ 0.006 | 0.529 $±$ 0.002 | 0.536 $±$ 0.004 | 0.310 $±$ 0.005 | 0.735 $±$ 0.027 | 0.635 $±$ 0.005 | 0.558 $±$ 0.003 | | | HC-SMoE | 0.478 $±$ 0.006 | 0.722 $±$ 0.006 | 0.863 $±$ 0.003 | 0.714 $±$ 0.000 | 0.684 $±$ 0.002 | 0.417 $±$ 0.001 | 0.805 $±$ 0.004 | 0.710 $±$ 0.004 | 0.674 $±$ 0.001 | | | | | Pruning | Frequency | 0.401 $±$ 0.011 | 0.600 $±$ 0.016 | 0.847 $±$ 0.003 | 0.593 $±$ 0.005 | 0.600 $±$ 0.004 | 0.342 $±$ 0.012 | 0.781 $±$ 0.002 | 0.637 $±$ 0.005 | 0.600 $±$ 0.005 | | | | EAN | 0.406 $±$ 0.007 | 0.603 $±$ 0.014 | 0.847 $±$ 0.005 | 0.607 $±$ 0.006 | 0.600 $±$ 0.002 | 0.337 $±$ 0.003 | 0.764 $±$ 0.002 | 0.660 $±$ 0.009 | 0.603 $±$ 0.004 | | | | | REAP | 0.481 $±$ 0.005 | 0.720 $±$ 0.005 | 0.852 $±$ 0.003 | 0.706 $±$ 0.006 | 0.674 $±$ 0.002 | 0.405 $±$ 0.005 | 0.813 $±$ 0.006 | 0.701 $±$ 0.008 | 0.669 $±$ 0.003 | | | | | 50% | Merging | M-SMoE | 0.278 $±$ 0.003 | 0.402 $±$ 0.003 | 0.753 $±$ 0.004 | 0.399 $±$ 0.002 | 0.366 $±$ 0.004 | 0.278 $±$ 0.002 | 0.586 $±$ 0.014 | 0.546 $±$ 0.004 | 0.451 $±$ 0.002 | | | HC-SMoE | 0.368 $±$ 0.002 | 0.593 $±$ 0.003 | 0.740 $±$ 0.003 | 0.473 $±$ 0.002 | 0.516 $±$ 0.003 | 0.301 $±$ 0.007 | 0.724 $±$ 0.004 | 0.620 $±$ 0.005 | 0.542 $±$ 0.001 | | | | | Pruning | Frequency | 0.285 $±$ 0.001 | 0.424 $±$ 0.002 | 0.779 $±$ 0.003 | 0.458 $±$ 0.003 | 0.397 $±$ 0.002 | 0.286 $±$ 0.004 | 0.659 $±$ 0.012 | 0.570 $±$ 0.009 | 0.483 $±$ 0.001 | | | | EAN | 0.296 $±$ 0.006 | 0.426 $±$ 0.009 | 0.759 $±$ 0.007 | 0.471 $±$ 0.002 | 0.443 $±$ 0.001 | 0.291 $±$ 0.009 | 0.668 $±$ 0.020 | 0.589 $±$ 0.009 | 0.493 $±$ 0.003 | | | | | REAP | 0.344 $±$ 0.004 | 0.504 $±$ 0.008 | 0.745 $±$ 0.005 | 0.489 $±$ 0.013 | 0.507 $±$ 0.005 | 0.311 $±$ 0.003 | 0.625 $±$ 0.031 | 0.623 $±$ 0.007 | 0.518 $±$ 0.004 | | | | | Mixtral-8x7B- Instruct-v0.1 | Baseline | 0.650 | 0.842 | 0.887 | 0.861 | 0.691 | 0.496 | 0.722 | 0.740 | 0.736 | | | | 25% | Merging | M-SMoE | 0.532 $±$ 0.004 | 0.769 $±$ 0.007 | 0.847 $±$ 0.001 | 0.747 $±$ 0.002 | 0.553 $±$ 0.001 | 0.429 $±$ 0.008 | 0.632 $±$ 0.010 | 0.656 $±$ 0.004 | 0.646 $±$ 0.001 | | | HC-SMoE | 0.590 $±$ 0.004 | 0.797 $±$ 0.004 | 0.869 $±$ 0.003 | 0.835 $±$ 0.002 | 0.626 $±$ 0.000 | 0.482 $±$ 0.004 | 0.703 $±$ 0.012 | 0.731 $±$ 0.007 | 0.704 $±$ 0.001 | | | | | Pruning | Frequency | 0.616 $±$ 0.014 | 0.826 $±$ 0.007 | 0.875 $±$ 0.001 | 0.825 $±$ 0.002 | 0.637 $±$ 0.003 | 0.451 $±$ 0.003 | 0.706 $±$ 0.017 | 0.692 $±$ 0.005 | 0.704 $±$ 0.002 | | | | EAN | 0.607 $±$ 0.004 | 0.831 $±$ 0.001 | 0.884 $±$ 0.001 | 0.836 $±$ 0.001 | 0.646 $±$ 0.002 | 0.484 $±$ 0.005 | 0.700 $±$ 0.004 | 0.732 $±$ 0.004 | 0.715 $±$ 0.000 | | | | | REAP | 0.611 $±$ 0.003 | 0.825 $±$ 0.001 | 0.874 $±$ 0.002 | 0.830 $±$ 0.002 | 0.643 $±$ 0.001 | 0.475 $±$ 0.006 | 0.761 $±$ 0.002 | 0.718 $±$ 0.001 | 0.717 $±$ 0.001 | | | | | 50% | Merging | M-SMoE | 0.446 $±$ 0.005 | 0.700 $±$ 0.001 | 0.788 $±$ 0.003 | 0.630 $±$ 0.002 | 0.430 $±$ 0.001 | 0.386 $±$ 0.003 | 0.570 $±$ 0.000 | 0.596 $±$ 0.005 | 0.568 $±$ 0.001 | | | HC-SMoE | 0.539 $±$ 0.003 | 0.759 $±$ 0.000 | 0.851 $±$ 0.001 | 0.791 $±$ 0.001 | 0.543 $±$ 0.000 | 0.442 $±$ 0.000 | 0.700 $±$ 0.004 | 0.712 $±$ 0.002 | 0.667 $±$ 0.001 | | | | | Pruning | Frequency | 0.541 $±$ 0.004 | 0.781 $±$ 0.003 | 0.824 $±$ 0.013 | 0.759 $±$ 0.002 | 0.516 $±$ 0.002 | 0.411 $±$ 0.006 | 0.708 $±$ 0.023 | 0.650 $±$ 0.005 | 0.649 $±$ 0.004 | | | | EAN | 0.551 $±$ 0.014 | 0.774 $±$ 0.008 | 0.859 $±$ 0.004 | 0.794 $±$ 0.002 | 0.550 $±$ 0.006 | 0.452 $±$ 0.014 | 0.717 $±$ 0.023 | 0.693 $±$ 0.008 | 0.674 $±$ 0.005 | | | | | REAP | 0.544 $±$ 0.005 | 0.785 $±$ 0.005 | 0.837 $±$ 0.003 | 0.778 $±$ 0.002 | 0.554 $±$ 0.001 | 0.462 $±$ 0.005 | 0.715 $±$ 0.013 | 0.679 $±$ 0.005 | 0.669 $±$ 0.001 | | | | | Llama-4-Scout- 17B-16E- Instruct | Baseline | 0.627 | 0.848 | 0.879 | 0.823 | 0.803 | 0.462 | 0.765 | 0.692 | 0.738 | | | | 25% | Merging | M-SMoE | 0.573 | 0.802 | 0.872 | 0.752 | 0.719 | 0.434 | 0.769 | 0.671 | 0.699 | | | HC-SMoE | 0.588 | 0.814 | 0.876 | 0.779 | 0.720 | 0.424 | 0.729 | 0.695 | 0.703 | | | | | Pruning | Frequency | 0.584 | 0.817 | 0.876 | 0.779 | 0.733 | 0.438 | 0.773 | 0.691 | 0.711 | | | | EAN | 0.582 | 0.816 | 0.872 | 0.777 | 0.735 | 0.446 | 0.791 | 0.679 | 0.712 | | | | | REAP | 0.594 | 0.830 | 0.872 | 0.788 | 0.756 | 0.452 | 0.769 | 0.683 | 0.718 | | | | | 50% | Merging | M-SMoE | 0.498 | 0.717 | 0.856 | 0.676 | 0.609 | 0.388 | 0.787 | 0.665 | 0.649 | | | HC-SMoE | 0.526 | 0.781 | 0.862 | 0.718 | 0.628 | 0.386 | 0.726 | 0.660 | 0.661 | | | | | Pruning | Frequency | 0.518 | 0.734 | 0.860 | 0.704 | 0.652 | 0.398 | 0.765 | 0.657 | 0.661 | | | | EAN | 0.510 | 0.750 | 0.857 | 0.712 | 0.650 | 0.398 | 0.762 | 0.662 | 0.663 | | | | | REAP | 0.561 | 0.802 | 0.869 | 0.745 | 0.682 | 0.432 | 0.762 | 0.664 | 0.689 | | | | | GLM-4.5-Air | Baseline | 0.619 | 0.825 | 0.882 | 0.858 | 0.789 | 0.478 | 0.747 | 0.776 | 0.747 | | | | 25% | Merging | M-SMoE | 0.429 | 0.651 | 0.808 | 0.671 | 0.578 | 0.362 | 0.578 | 0.695 | 0.596 | | | HC-SMoE | 0.577 | 0.782 | 0.860 | 0.815 | 0.722 | 0.458 | 0.668 | 0.755 | 0.704 | | | | | Pruning | Frequency | 0.493 | 0.715 | 0.827 | 0.732 | 0.653 | 0.422 | 0.614 | 0.725 | 0.648 | | | | EAN | 0.492 | 0.705 | 0.805 | 0.736 | 0.656 | 0.368 | 0.603 | 0.730 | 0.637 | | | | | REAP | 0.555 | 0.756 | 0.813 | 0.796 | 0.701 | 0.434 | 0.643 | 0.724 | 0.678 | | | | | 50% | Merging | M-SMoE | 0.291 | 0.452 | 0.693 | 0.433 | 0.382 | 0.266 | 0.484 | 0.551 | 0.444 | | | HC-SMoE | 0.428 | 0.671 | 0.761 | 0.590 | 0.524 | 0.318 | 0.603 | 0.613 | 0.564 | | | | | Pruning | Frequency | 0.334 | 0.535 | 0.767 | 0.566 | 0.478 | 0.288 | 0.567 | 0.635 | 0.521 | | | | EAN | 0.358 | 0.530 | 0.682 | 0.573 | 0.489 | 0.300 | 0.516 | 0.635 | 0.511 | | | | | REAP | 0.427 | 0.604 | 0.662 | 0.642 | 0.569 | 0.318 | 0.606 | 0.640 | 0.559 | | | | | Qwen3-Coder- 480B-A35B- Instruct-FP8 | Baseline | 0.644 | 0.822 | 0.906 | 0.841 | 0.850 | 0.468 | 0.751 | 0.717 | 0.750 | | | | 25% | Pruning | Frequency | 0.443 | 0.673 | 0.845 | 0.651 | 0.621 | 0.280 | 0.704 | 0.632 | 0.606 | | | EAN | 0.555 | 0.766 | 0.891 | 0.769 | 0.795 | 0.404 | 0.747 | 0.691 | 0.702 | | | | | REAP | 0.635 | 0.824 | 0.900 | 0.841 | 0.836 | 0.466 | 0.754 | 0.725 | 0.748 | | | | | 50% | Pruning | Frequency | 0.314 | 0.470 | 0.791 | 0.502 | 0.451 | 0.262 | 0.679 | 0.580 | 0.506 | | | EAN | 0.402 | 0.596 | 0.858 | 0.629 | 0.615 | 0.216 | 0.744 | 0.666 | 0.591 | | | | | REAP | 0.546 | 0.772 | 0.872 | 0.756 | 0.696 | 0.430 | 0.762 | 0.701 | 0.692 | | | | | Kimi-K2- Instruct- W4A16 | Baseline | 0.712 | 0.879 | 0.913 | 0.765 | 0.872 | 0.504 | 0.783 | 0.811 | 0.780 | | | | 25% | Pruning | Frequency | 0.518 | 0.771 | 0.825 | 0.787 | 0.242 | 0.420 | 0.653 | 0.613 | 0.604 | | | EAN | 0.615 | 0.819 | 0.893 | 0.843 | 0.500 | 0.446 | 0.762 | 0.743 | 0.703 | | | | | REAP | 0.671 | 0.854 | 0.907 | 0.860 | 0.809 | 0.470 | 0.805 | 0.809 | 0.773 | | | | | 50% | Pruning | Frequency | 0.285 | 0.498 | 0.620 | 0.436 | 0.241 | 0.314 | 0.617 | 0.500 | 0.439 | | | EAN | 0.426 | 0.682 | 0.863 | 0.663 | 0.324 | 0.356 | 0.726 | 0.659 | 0.587 | | | | | REAP | 0.476 | 0.661 | 0.883 | 0.643 | 0.636 | 0.350 | 0.816 | 0.681 | 0.643 | | | | Table A5: Detailed benchmark results for non-agentic code generation tasks. Eval+ is the average of MBPP, MBPP+, HE, HE+. The Code Avg column is the average of Eval+ and LiveCodeBench (LiveCode). | Model | Compression | Technique | Method | HE | HE+ | MBPP | MBPP+ | Eval+ | LiveCode | Code Avg | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | ERNIE-4.5-21B- A3B-PT | Baseline | 0.902 | 0.866 | 0.910 | 0.765 | 0.861 | 0.231 | 0.546 | | | | 25% | Merging | M-SMoE | 0.774 $±$ 0.011 | 0.730 $±$ 0.009 | 0.768 $±$ 0.015 | 0.647 $±$ 0.017 | 0.730 $±$ 0.005 | 0.194 $±$ 0.022 | 0.462 $±$ 0.011 | | | HC-SMoE | 0.837 $±$ 0.007 | 0.805 $±$ 0.000 | 0.827 $±$ 0.003 | 0.696 $±$ 0.008 | 0.791 $±$ 0.004 | 0.207 $±$ 0.008 | 0.499 $±$ 0.003 | | | | | Pruning | Frequency | 0.890 $±$ 0.006 | 0.846 $±$ 0.009 | 0.837 $±$ 0.010 | 0.709 $±$ 0.010 | 0.820 $±$ 0.006 | 0.151 $±$ 0.096 | 0.486 $±$ 0.045 | | | | EAN | 0.890 $±$ 0.006 | 0.848 $±$ 0.011 | 0.840 $±$ 0.006 | 0.727 $±$ 0.004 | 0.826 $±$ 0.004 | 0.161 $±$ 0.111 | 0.494 $±$ 0.054 | | | | | REAP | 0.892 $±$ 0.009 | 0.854 $±$ 0.012 | 0.876 $±$ 0.000 | 0.738 $±$ 0.003 | 0.840 $±$ 0.005 | 0.167 $±$ 0.124 | 0.504 $±$ 0.060 | | | | | 50% | Merging | M-SMoE | 0.104 $±$ 0.022 | 0.100 $±$ 0.029 | 0.239 $±$ 0.036 | 0.207 $±$ 0.040 | 0.162 $±$ 0.012 | 0.024 $±$ 0.008 | 0.093 $±$ 0.008 | | | HC-SMoE | 0.425 $±$ 0.004 | 0.404 $±$ 0.007 | 0.608 $±$ 0.018 | 0.511 $±$ 0.011 | 0.487 $±$ 0.008 | 0.082 $±$ 0.015 | 0.285 $±$ 0.009 | | | | | Pruning | Frequency | 0.699 $±$ 0.031 | 0.640 $±$ 0.022 | 0.696 $±$ 0.014 | 0.584 $±$ 0.006 | 0.655 $±$ 0.015 | 0.083 $±$ 0.066 | 0.369 $±$ 0.025 | | | | EAN | 0.675 $±$ 0.019 | 0.642 $±$ 0.009 | 0.713 $±$ 0.015 | 0.591 $±$ 0.016 | 0.655 $±$ 0.014 | 0.112 $±$ 0.064 | 0.384 $±$ 0.035 | | | | | REAP | 0.797 $±$ 0.009 | 0.764 $±$ 0.007 | 0.767 $±$ 0.017 | 0.644 $±$ 0.013 | 0.743 $±$ 0.008 | 0.137 $±$ 0.119 | 0.440 $±$ 0.064 | | | | | Qwen3-30B-A3B | Baseline | 0.927 | 0.884 | 0.881 | 0.743 | 0.859 | 0.302 | 0.581 | | | | 25% | Merging | M-SMoE | 0.878 $±$ 0.012 | 0.833 $±$ 0.007 | 0.849 $±$ 0.007 | 0.728 $±$ 0.007 | 0.822 $±$ 0.004 | 0.293 $±$ 0.017 | 0.558 $±$ 0.006 | | | HC-SMoE | 0.866 $±$ 0.011 | 0.805 $±$ 0.016 | 0.832 $±$ 0.006 | 0.698 $±$ 0.005 | 0.800 $±$ 0.004 | 0.258 $±$ 0.000 | 0.529 $±$ 0.002 | | | | | Pruning | Frequency | 0.921 $±$ 0.006 | 0.874 $±$ 0.007 | 0.868 $±$ 0.000 | 0.735 $±$ 0.003 | 0.849 $±$ 0.004 | 0.302 $±$ 0.011 | 0.576 $±$ 0.004 | | | | EAN | 0.909 $±$ 0.006 | 0.864 $±$ 0.004 | 0.859 $±$ 0.009 | 0.729 $±$ 0.008 | 0.840 $±$ 0.004 | 0.311 $±$ 0.018 | 0.576 $±$ 0.010 | | | | | REAP | 0.917 $±$ 0.007 | 0.876 $±$ 0.004 | 0.853 $±$ 0.002 | 0.727 $±$ 0.006 | 0.843 $±$ 0.002 | 0.308 $±$ 0.015 | 0.575 $±$ 0.008 | | | | | 50% | Merging | M-SMoE | 0.687 $±$ 0.013 | 0.638 $±$ 0.004 | 0.618 $±$ 0.004 | 0.541 $±$ 0.007 | 0.621 $±$ 0.006 | 0.205 $±$ 0.019 | 0.413 $±$ 0.007 | | | HC-SMoE | 0.577 $±$ 0.023 | 0.541 $±$ 0.013 | 0.631 $±$ 0.010 | 0.546 $±$ 0.004 | 0.574 $±$ 0.010 | 0.185 $±$ 0.018 | 0.379 $±$ 0.005 | | | | | Pruning | Frequency | 0.787 $±$ 0.016 | 0.756 $±$ 0.022 | 0.692 $±$ 0.016 | 0.579 $±$ 0.016 | 0.704 $±$ 0.017 | 0.236 $±$ 0.025 | 0.470 $±$ 0.021 | | | | EAN | 0.886 $±$ 0.025 | 0.837 $±$ 0.020 | 0.798 $±$ 0.006 | 0.669 $±$ 0.008 | 0.798 $±$ 0.013 | 0.306 $±$ 0.003 | 0.552 $±$ 0.005 | | | | | REAP | 0.919 $±$ 0.007 | 0.870 $±$ 0.004 | 0.805 $±$ 0.009 | 0.692 $±$ 0.008 | 0.821 $±$ 0.003 | 0.293 $±$ 0.003 | 0.557 $±$ 0.001 | | | | | Mixtral-8x7B- Instruct-v0.1 | Baseline | 0.524 | 0.476 | 0.556 | 0.463 | 0.505 | 0.123 | 0.314 | | | | 25% | Merging | M-SMoE | 0.315 $±$ 0.007 | 0.270 $±$ 0.015 | 0.446 $±$ 0.007 | 0.380 $±$ 0.015 | 0.353 $±$ 0.008 | 0.033 $±$ 0.010 | 0.193 $±$ 0.008 | | | HC-SMoE | 0.439 $±$ 0.028 | 0.386 $±$ 0.020 | 0.530 $±$ 0.022 | 0.441 $±$ 0.007 | 0.449 $±$ 0.005 | 0.110 $±$ 0.010 | 0.279 $±$ 0.002 | | | | | Pruning | Frequency | 0.400 $±$ 0.034 | 0.358 $±$ 0.035 | 0.541 $±$ 0.006 | 0.453 $±$ 0.012 | 0.438 $±$ 0.018 | 0.099 $±$ 0.014 | 0.269 $±$ 0.004 | | | | EAN | 0.413 $±$ 0.027 | 0.366 $±$ 0.024 | 0.477 $±$ 0.009 | 0.409 $±$ 0.013 | 0.416 $±$ 0.015 | 0.111 $±$ 0.006 | 0.264 $±$ 0.006 | | | | | REAP | 0.439 $±$ 0.018 | 0.370 $±$ 0.007 | 0.535 $±$ 0.011 | 0.452 $±$ 0.011 | 0.449 $±$ 0.002 | 0.102 $±$ 0.010 | 0.275 $±$ 0.005 | | | | | 50% | Merging | M-SMoE | 0.085 $±$ 0.026 | 0.076 $±$ 0.022 | 0.139 $±$ 0.121 | 0.118 $±$ 0.102 | 0.091 $±$ 0.079 | 0.004 $±$ 0.006 | 0.047 $±$ 0.037 | | | HC-SMoE | 0.175 $±$ 0.015 | 0.146 $±$ 0.000 | 0.335 $±$ 0.026 | 0.282 $±$ 0.031 | 0.235 $±$ 0.018 | 0.013 $±$ 0.008 | 0.124 $±$ 0.008 | | | | | Pruning | Frequency | 0.187 $±$ 0.015 | 0.148 $±$ 0.007 | 0.342 $±$ 0.016 | 0.287 $±$ 0.012 | 0.241 $±$ 0.007 | 0.023 $±$ 0.004 | 0.132 $±$ 0.003 | | | | EAN | 0.220 $±$ 0.006 | 0.189 $±$ 0.006 | 0.375 $±$ 0.020 | 0.325 $±$ 0.015 | 0.277 $±$ 0.005 | 0.031 $±$ 0.011 | 0.154 $±$ 0.007 | | | | | REAP | 0.232 $±$ 0.018 | 0.193 $±$ 0.013 | 0.274 $±$ 0.106 | 0.241 $±$ 0.087 | 0.235 $±$ 0.056 | 0.035 $±$ 0.003 | 0.135 $±$ 0.027 | | | | | Llama-4-Scout- 17B-16E- Instruct | Baseline | 0.829 | 0.768 | 0.788 | 0.640 | 0.757 | 0.341 | 0.549 | | | | 25% | Merging | M-SMoE | 0.823 | 0.762 | 0.786 | 0.635 | 0.752 | 0.324 | 0.538 | | | HC-SMoE | 0.787 | 0.738 | 0.735 | 0.587 | 0.712 | 0.148 | 0.430 | | | | | Pruning | Frequency | 0.835 | 0.768 | 0.788 | 0.630 | 0.755 | 0.317 | 0.536 | | | | EAN | 0.823 | 0.762 | 0.804 | 0.648 | 0.759 | 0.328 | 0.544 | | | | | REAP | 0.829 | 0.787 | 0.788 | 0.622 | 0.756 | 0.242 | 0.499 | | | | | 50% | Merging | M-SMoE | 0.787 | 0.732 | 0.762 | 0.614 | 0.723 | 0.187 | 0.455 | | | HC-SMoE | 0.604 | 0.530 | 0.500 | 0.399 | 0.508 | 0.077 | 0.293 | | | | | Pruning | Frequency | 0.823 | 0.756 | 0.751 | 0.595 | 0.731 | 0.223 | 0.477 | | | | EAN | 0.805 | 0.744 | 0.754 | 0.601 | 0.726 | 0.209 | 0.468 | | | | | REAP | 0.841 | 0.768 | 0.762 | 0.624 | 0.749 | 0.248 | 0.499 | | | | | GLM-4.5-Air | Baseline | 0.848 | 0.829 | 0.860 | 0.743 | 0.820 | 0.374 | 0.597 | | | | 25% | Merging | M-SMoE | 0.866 | 0.793 | 0.807 | 0.659 | 0.781 | 0.330 | 0.555 | | | HC-SMoE | 0.872 | 0.805 | 0.825 | 0.669 | 0.793 | 0.363 | 0.578 | | | | | Pruning | Frequency | 0.848 | 0.811 | 0.854 | 0.706 | 0.805 | 0.341 | 0.573 | | | | EAN | 0.872 | 0.817 | 0.876 | 0.720 | 0.821 | 0.374 | 0.597 | | | | | REAP | 0.866 | 0.805 | 0.828 | 0.677 | 0.794 | 0.390 | 0.592 | | | | | 50% | Merging | M-SMoE | 0.518 | 0.500 | 0.519 | 0.437 | 0.493 | 0.099 | 0.296 | | | HC-SMoE | 0.707 | 0.659 | 0.706 | 0.577 | 0.662 | 0.220 | 0.441 | | | | | Pruning | Frequency | 0.628 | 0.573 | 0.534 | 0.450 | 0.546 | 0.104 | 0.325 | | | | EAN | 0.841 | 0.780 | 0.807 | 0.661 | 0.773 | 0.253 | 0.513 | | | | | REAP | 0.878 | 0.841 | 0.712 | 0.587 | 0.755 | 0.352 | 0.553 | | | | | Qwen3-Coder- 480B-A35B- Instruct-FP8 | Baseline | 0.951 | 0.890 | 0.923 | 0.791 | 0.889 | 0.431 $±$ 0.011 | 0.660 | | | | 25% | Pruning | Frequency | 0.884 | 0.805 | 0.810 | 0.669 | 0.792 | 0.296 $±$ 0.017 | 0.544 | | | EAN | 0.939 | 0.878 | 0.911 | 0.775 | 0.876 | 0.419 $±$ 0.015 | 0.647 | | | | | REAP | 0.957 | 0.890 | 0.917 | 0.772 | 0.884 | 0.416 $±$ 0.013 | 0.650 | | | | | 50% | Pruning | Frequency | 0.020 | 0.012 | 0.007 | 0.003 | 0.011 | 0.012 $±$ 0.001 | 0.011 | | | EAN | 0.915 | 0.841 | 0.854 | 0.714 | 0.831 | 0.382 $±$ 0.012 | 0.607 | | | | | REAP | 0.939 | 0.872 | 0.910 | 0.772 | 0.873 | 0.415 $±$ 0.015 | 0.644 | | | | | Kimi-K2- Instruct- W4A16 | Baseline | 0.963 | 0.921 | 0.913 | 0.735 | 0.883 | 0.434 | 0.659 | | | | 25% | Pruning | Frequency | 0.530 | 0.463 | 0.595 | 0.508 | 0.524 | 0.082 | 0.303 | | | EAN | 0.909 | 0.860 | 0.857 | 0.698 | 0.831 | 0.379 | 0.605 | | | | | REAP | 0.957 | 0.921 | 0.918 | 0.759 | 0.889 | 0.440 | 0.664 | | | | | 50% | Pruning | Frequency | 0.098 | 0.079 | 0.175 | 0.146 | 0.124 | 0.000 | 0.062 | | | EAN | 0.866 | 0.811 | 0.780 | 0.632 | 0.772 | 0.253 | 0.513 | | | | | REAP | 0.915 | 0.884 | 0.899 | 0.754 | 0.863 | 0.429 | 0.646 | | | | Table A6: C4 calibrated results for coding and MC tasks. | | Coding | MC | | | | | | | | | | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | Model | Compression | Technique | Method | Eval+ | LiveCode | Code Avg | ARC-c | ARC-e | BoolQ | Hellaswag | MMLU | OBQA | RTE | WinoG. | MC Avg | | ERNIE-4.5-21B- A3B-PT | Baseline | 0.861 | 0.231 | 0.546 | 0.564 | 0.782 | 0.873 | 0.813 | 0.737 | 0.462 | 0.812 | 0.724 | 0.721 | | | | 25% | Merging | M-SMoE | 0.065 | 0.016 | 0.041 | 0.497 | 0.729 | 0.860 | 0.723 | 0.602 | 0.424 | 0.801 | 0.699 | 0.667 | | | HC-SMoE | 0.403 | 0.099 | 0.251 | 0.515 | 0.728 | 0.860 | 0.745 | 0.649 | 0.428 | 0.794 | 0.694 | 0.677 | | | | | Pruning | Frequency | 0.274 | 0.000 | 0.137 | 0.515 | 0.735 | 0.841 | 0.719 | 0.588 | 0.382 | 0.791 | 0.683 | 0.657 | | | | EAN | 0.282 | 0.000 | 0.141 | 0.528 | 0.750 | 0.853 | 0.790 | 0.558 | 0.442 | 0.783 | 0.706 | 0.676 | | | | | REAP | 0.242 | 0.023 | 0.133 | 0.490 | 0.716 | 0.855 | 0.783 | 0.656 | 0.452 | 0.809 | 0.723 | 0.685 | | | | | 50% | Merging | M-SMoE | 0.000 | 0.000 | 0.000 | 0.297 | 0.460 | 0.674 | 0.449 | 0.312 | 0.280 | 0.671 | 0.575 | 0.465 | | | HC-SMoE | 0.000 | 0.000 | 0.000 | 0.409 | 0.615 | 0.666 | 0.515 | 0.489 | 0.290 | 0.632 | 0.580 | 0.524 | | | | | Pruning | Frequency | 0.000 | 0.000 | 0.000 | 0.393 | 0.625 | 0.717 | 0.569 | 0.496 | 0.324 | 0.758 | 0.619 | 0.563 | | | | EAN | 0.007 | 0.003 | 0.005 | 0.451 | 0.676 | 0.742 | 0.687 | 0.474 | 0.398 | 0.736 | 0.691 | 0.607 | | | | | REAP | 0.033 | 0.000 | 0.016 | 0.406 | 0.612 | 0.754 | 0.654 | 0.468 | 0.396 | 0.718 | 0.656 | 0.583 | | | | | Qwen3-30B-A3B | Baseline | 0.859 | 0.302 | 0.581 | 0.563 | 0.790 | 0.887 | 0.778 | 0.779 | 0.454 | 0.816 | 0.702 | 0.721 | | | | 25% | Merging | M-SMoE | 0.000 | 0.000 | 0.000 | 0.551 | 0.768 | 0.883 | 0.761 | 0.733 | 0.418 | 0.848 | 0.701 | 0.708 | | | HC-SMoE | 0.831 | 0.269 | 0.550 | 0.470 | 0.713 | 0.833 | 0.622 | 0.646 | 0.376 | 0.805 | 0.665 | 0.641 | | | | | Pruning | Frequency | 0.000 | 0.000 | 0.000 | 0.548 | 0.789 | 0.889 | 0.775 | 0.735 | 0.438 | 0.801 | 0.694 | 0.709 | | | | EAN | 0.000 | 0.000 | 0.000 | 0.569 | 0.802 | 0.889 | 0.774 | 0.735 | 0.438 | 0.801 | 0.697 | 0.713 | | | | | REAP | 0.735 | 0.227 | 0.481 | 0.557 | 0.781 | 0.872 | 0.746 | 0.718 | 0.436 | 0.794 | 0.704 | 0.701 | | | | | 50% | Merging | M-SMoE | 0.000 | 0.000 | 0.000 | 0.262 | 0.348 | 0.693 | 0.479 | 0.237 | 0.290 | 0.523 | 0.542 | 0.422 | | | HC-SMoE | 0.728 | 0.209 | 0.468 | 0.316 | 0.495 | 0.715 | 0.354 | 0.422 | 0.282 | 0.603 | 0.536 | 0.465 | | | | | Pruning | Frequency | 0.000 | 0.000 | 0.000 | 0.349 | 0.488 | 0.782 | 0.672 | 0.503 | 0.364 | 0.588 | 0.619 | 0.545 | | | | EAN | 0.000 | 0.000 | 0.000 | 0.480 | 0.736 | 0.876 | 0.760 | 0.607 | 0.424 | 0.762 | 0.694 | 0.667 | | | | | REAP | 0.006 | 0.000 | 0.003 | 0.421 | 0.640 | 0.837 | 0.653 | 0.495 | 0.388 | 0.704 | 0.635 | 0.596 | | | | | Mixtral-8x7B- Instruct-v0.1 | Baseline | 0.505 | 0.123 | 0.314 | 0.650 | 0.842 | 0.887 | 0.861 | 0.691 | 0.496 | 0.722 | 0.740 | 0.736 | | | | 25% | Merging | M-SMoE | 0.320 | 0.044 | 0.182 | 0.532 | 0.775 | 0.828 | 0.746 | 0.529 | 0.424 | 0.603 | 0.632 | 0.634 | | | HC-SMoE | 0.420 | 0.121 | 0.271 | 0.608 | 0.811 | 0.876 | 0.838 | 0.631 | 0.484 | 0.736 | 0.726 | 0.714 | | | | | Pruning | Frequency | 0.396 | 0.070 | 0.233 | 0.612 | 0.816 | 0.868 | 0.836 | 0.593 | 0.482 | 0.675 | 0.739 | 0.703 | | | | EAN | 0.399 | 0.092 | 0.246 | 0.613 | 0.814 | 0.875 | 0.842 | 0.613 | 0.498 | 0.690 | 0.733 | 0.710 | | | | | REAP | 0.415 | 0.077 | 0.246 | 0.606 | 0.807 | 0.875 | 0.835 | 0.633 | 0.486 | 0.791 | 0.709 | 0.718 | | | | | 50% | Merging | M-SMoE | 0.000 | 0.000 | 0.000 | 0.260 | 0.460 | 0.614 | 0.395 | 0.240 | 0.302 | 0.527 | 0.526 | 0.416 | | | HC-SMoE | 0.174 | 0.033 | 0.103 | 0.540 | 0.764 | 0.862 | 0.795 | 0.544 | 0.448 | 0.675 | 0.709 | 0.667 | | | | | Pruning | Frequency | 0.173 | 0.008 | 0.090 | 0.504 | 0.739 | 0.793 | 0.771 | 0.463 | 0.426 | 0.675 | 0.646 | 0.627 | | | | EAN | 0.139 | 0.008 | 0.074 | 0.550 | 0.756 | 0.842 | 0.804 | 0.529 | 0.460 | 0.726 | 0.716 | 0.673 | | | | | REAP | 0.167 | 0.012 | 0.089 | 0.525 | 0.774 | 0.856 | 0.794 | 0.533 | 0.454 | 0.751 | 0.688 | 0.672 | | | | Table A7: $\tau^{2}$ -bench results with REAP compression across different benchmark domains on Qwen3-480B-A35B-Coder-FP8. | Dataset | Compression | Method | passˆ1 | passˆ2 | passˆ3 | | --- | --- | --- | --- | --- | --- | | Retail | Baseline | 0.643 | 0.544 | 0.500 | | | 25% | REAP | 0.661 | 0.535 | 0.465 | | | 50% | REAP | 0.632 | 0.515 | 0.456 | | | Airline | Baseline | 0.460 | 0.340 | 0.280 | | | 25% | REAP | 0.487 | 0.367 | 0.320 | | | 50% | REAP | 0.447 | 0.333 | 0.280 | | | Telecom | Baseline | 0.500 | 0.398 | 0.325 | | | 25% | REAP | 0.529 | 0.456 | 0.421 | | | 50% | REAP | 0.471 | 0.339 | 0.263 | | Figure ˜ A5 plots non-agentic coding and MC accuracy versus compressed model size. Figure ˜ 6(a) depict the proportion of singleton clusters for HC-SMoE and M-SMoE. Figure ˜ 6(b) plots accuracy vs. maximum cluster sizes when the maximum cardinality of clusters is restricted. Figures ˜ A7 and A8 show the importance of using domain-specific calibration data, particularly at high compression ratios. Table ˜ A7 presents the complete $\tau^{2}$ -bench results across three domains (Retail, Airline, and Telecom) for the baseline model and REAP compression at 25% and 50% levels. The results show passˆk metrics for k=1, 2, and 3, demonstrating the impact of pruning on evaluating conversational agents, specifically designed to test their ability to collaborate with a user in real-world scenarios. <details> <summary>2510.13999v1/x17.png Details</summary>  ### Visual Description # Technical Analysis of Chart: Non-Agentic Code Accuracy vs. MC Accuracy Across Model Sizes ## Chart Structure - **Two-panel layout** comparing performance metrics across model parameter scales - **X-axis**: Log Scaled Total Parameters (in billions) [10¹, 10², 10³] - **Y-axes**: - Left: Non-Agentic Code Accuracy (%) - Right: MC Accuracy (%) ## Legend Analysis - **Position**: Right side of both panels - **Color-Coded Methods**: - Baseline: Black squares (■) - Pruning Methods: Blue diamonds (◆) - REAP (ours): Blue dashed line with stars (★) - EAN: Red dashed line with triangles (▼) - Frequency: Green dashed line with diamonds (◆) - Merging Methods: Yellow dashed line with triangles (▼) - HC-SMoE: Orange dashed line with squares (■) - M-SMoE: Light blue dashed line with triangles (▼) ## Model-Specific Markers | Model Name | Marker | Color | |-------------------------------------|--------|-------------| | ERNIE-4.5-21B-A3B | ● | Black | | Mixtral-8x7B-Instruct-v0.1 | ▼ | Red | | LLaMA-4-Scout-17B-16E-Instruct | ● | Blue | | GLM-4.5-Air | ● | Green | | Qwen3-30B-A3B | ● | Orange | | Qwen3-Coder-480B-A35B-Instruct-FP8 | ● | Purple | | Kimi-K2-Instruct-W4A16 | ● | Pink | ## Key Trends ### Left Panel: Non-Agentic Code Accuracy 1. **Baseline (■)**: - Trend: Gradual increase from ~40% (10¹ params) to ~60% (10³ params) - Notable: Steady improvement across all parameter scales 2. **REAP (◆)**: - Trend: Sharp upward trajectory - Peak: ~65% at 10³ parameters - Outperforms baseline by 10%+ at largest scale 3. **EAN (▼)**: - Trend: Moderate growth with plateau at 10² params - Final value: ~55% at 10³ params 4. **Frequency (◆)**: - Trend: Volatile performance with significant drop at 10² params - Recovery: Sharp increase at 10³ params to ~50% ### Right Panel: MC Accuracy 1. **Baseline (■)**: - Trend: Consistent growth from ~55% to ~70% - Linear progression across parameter scales 2. **REAP (◆)**: - Trend: Exponential improvement - Peak: ~75% at 10³ parameters - Outperforms baseline by 15%+ at largest scale 3. **EAN (▼)**: - Trend: Steady increase with minor fluctuations - Final value: ~65% at 10³ params 4. **Frequency (◆)**: - Trend: U-shaped curve - Dip: ~50% at 10² params - Recovery: ~60% at 10³ params ## Spatial Grounding - **Legend Position**: Right-aligned, occupying ~30% of panel width - **Data Point Alignment**: - All markers correspond exactly to legend colors - Example: Blue diamonds (◆) consistently represent REAP across both panels ## Data Reconstruction ### Non-Agentic Code Accuracy (%) | Parameters (B) | Baseline | REAP | EAN | Frequency | HC-SMoE | M-SMoE | |----------------|----------|------|-----|-----------|---------|--------| | 10¹ | 40 | 50 | 45 | 35 | 30 | 25 | | 10² | 55 | 58 | 52 | 48 | 45 | 40 | | 10³ | 60 | 65 | 55 | 50 | 55 | 45 | ### MC Accuracy (%) | Parameters (B) | Baseline | REAP | EAN | Frequency | HC-SMoE | M-SMoE | |----------------|----------|------|-----|-----------|---------|--------| | 10¹ | 55 | 60 | 58 | 50 | 45 | 40 | | 10² | 65 | 68 | 62 | 55 | 50 | 48 | | 10³ | 70 | 75 | 65 | 60 | 55 | 50 | ## Critical Observations 1. **REAP (ours)** consistently outperforms all other methods in both metrics 2. **Frequency** shows parameter-scale sensitivity with non-linear performance 3. **M-SMoE** maintains stable but suboptimal performance across all scales 4. **Baseline** demonstrates linear scaling behavior in both metrics </details> Figure A5: Coding and MC accuracy across all models vs. parameters. The benefits of REAP over other compression methods are evident at 50% compression. For large-scale SMoEs, REAP is near-lossless whereas the shortcomings of frequency-based pruning become apparent. <details> <summary>2510.13999v1/x18.png Details</summary>  ### Visual Description # Technical Document Extraction: Bar Chart Analysis ## Chart Type - **Bar Chart** comparing performance metrics across different models. ## Axes - **X-Axis (Categories)**: - ERNIE-4.5-21B-A3B-PT - Qwen3-30B-A3B - Mixtral-8x7B-Instruct-v0.1 - Llama-4-Scout-17B-16E-Instruct - GLM-4.5-Air - **Y-Axis (Values)**: - **Title**: "Singleton clusters (%)" - **Range**: 0% to 100% (increments of 20%) ## Legend - **HC-SMoE**: Blue bars - **M-SMoE**: Red bars ## Data Points 1. **ERNIE-4.5-21B-A3B-PT** - HC-SMoE: ~98% (error bar: ±2%) - M-SMoE: ~58% (error bar: ±6%) 2. **Qwen3-30B-A3B** - HC-SMoE: ~98% (error bar: ±2%) - M-SMoE: ~63% (error bar: ±5%) 3. **Mixtral-8x7B-Instruct-v0.1** - HC-SMoE: ~58% (error bar: ±7%) - M-SMoE: ~28% (error bar: ±10%) 4. **Llama-4-Scout-17B-16E-Instruct** - HC-SMoE: ~86% (error bar: ±4%) - M-SMoE: ~74% (error bar: ±6%) 5. **GLM-4.5-Air** - HC-SMoE: ~99% (error bar: ±1%) - M-SMoE: ~66% (error bar: ±5%) ## Key Trends - **HC-SMoE** consistently outperforms **M-SMoE** across all models. - **Highest Performance**: - HC-SMoE: GLM-4.5-Air (~99%) - M-SMoE: Llama-4-Scout-17B-16E-Instruct (~74%) - **Lowest Performance**: - HC-SMoE: Mixtral-8x7B-Instruct-v0.1 (~58%) - M-SMoE: Mixtral-8x7B-Instruct-v0.1 (~28%) - **Error Bar Observations**: - Larger variability in M-SMoE results (e.g., ±10% for Mixtral-8x7B-Instruct-v0.1). - Smaller error margins for HC-SMoE in most cases. ## Notes - Error bars represent standard deviation or confidence intervals (exact methodology unspecified). - No numerical values explicitly labeled on bars; percentages estimated visually. </details> (a) Singleton cluster proportion <details> <summary>2510.13999v1/x19.png Details</summary>  ### Visual Description # Chart Analysis: Accuracy Comparison by Max Cluster Size ## Chart Type Bar chart comparing accuracy percentages between two methods: **Coding** (blue) and **MC** (pink). ## Axes - **X-axis**: "Max cluster size" with categories: `None`, `32`, `16`, `8`, `4`, `2` - **Y-axis**: "Accuracy (%)" ranging from 0.0 to 0.45. ## Legend - **Blue**: Coding - **Pink**: MC ## Data Points | Max Cluster Size | Coding Accuracy (%) | MC Accuracy (%) | |-------------------|---------------------|-----------------| | None | ~0.41 | ~0.45 | | 32 | ~0.12 | ~0.45 | | 16 | ~0.11 | ~0.45 | | 8 | ~0.11 | ~0.45 | | 4 | ~0.21 | ~0.45 | | 2 | — | ~0.36 | ## Key Trends 1. **MC consistently outperforms Coding** across all max cluster sizes, with accuracy remaining near 0.45% for most categories. 2. **Coding accuracy varies significantly**: - Highest at `None` (~0.41%). - Lowest at `32`, `16`, and `8` (~0.11%). - Slight improvement at `4` (~0.21%). 3. **MC accuracy drops sharply** at `2` (~0.36%), the only category where Coding data is absent. ## Observations - No embedded text or additional annotations in the chart. - Data suggests MC is more robust to cluster size variations, while Coding performance degrades with larger clusters. </details> (b) Restricted cluster sizes Figure A6: (6(a)) Average proportion of singleton clusters vs. model for HC-SMoE and M-SMoE. We find that the clustering algorithms used by our baseline merging methods tend to generate a high proportion of singleton clusters containing just a single expert. In order to achieve the desired compression ratio, the large number of singletons conversely results in some clusters which contain many experts, in some cases $N/2+1$ experts for a layer with $N$ experts are grouped into a single cluster. (6(b)) Accuracy vs. maximum cluster size using M-SMoE to compress 50% of experts in Qwen3-30B. While MC accuracy remains stable up to a maximum cluster size of 4, generative coding capabilities are severely diminished by restricting the clustering algorithm. <details> <summary>2510.13999v1/x20.png Details</summary>  ### Visual Description # Technical Analysis of Coding Accuracy Chart ## Chart Overview The image contains three grouped bar charts comparing coding accuracy across different AI models and datasets under varying compression levels. Each chart represents a different model architecture, with bars segmented by compression percentage and dataset type. --- ## Chart Components ### Legend - **Location**: Right side of each chart - **Compression Levels**: - `0%`: Solid gray (dashed line in background) - `25%`: Crosshatched pattern - `50%`: Diagonal stripes - **Datasets**: - `c4`: Blue color - `CodeAlpaca`: Red color ### Axes - **X-axis**: Model names (REAP, EAN, Freq., HC-SMoE, M-SMoE) - **Y-axis**: Coding Accuracy (%) [0-60 range] - **Background**: Gray dashed line at ~55% (reference threshold) --- ## Chart 1: ERNIE-4.5-21B-A3B-PT | Model | c4 (0%) | c4 (25%) | c4 (50%) | CodeAlpaca (0%) | CodeAlpaca (25%) | CodeAlpaca (50%) | |------------|---------|----------|----------|------------------|-------------------|-------------------| | REAP | 14% | 15% | 45% | 30% | 40% | 50% | | EAN | 15% | 16% | 38% | 35% | 45% | 55% | | Freq. | 14% | 15% | 25% | 20% | 35% | 45% | | HC-SMoE | 25% | 28% | 30% | 25% | 40% | 50% | | M-SMoE | 4% | 5% | 9% | 10% | 20% | 30% | **Trends**: - REAP shows highest accuracy across all compression levels - CodeAlpaca dataset consistently outperforms c4 - M-SMoE has lowest performance in all configurations --- ## Chart 2: Qwen-30B-A3B | Model | c4 (0%) | c4 (25%) | c4 (50%) | CodeAlpaca (0%) | CodeAlpaca (25%) | CodeAlpaca (50%) | |------------|---------|----------|----------|------------------|-------------------|-------------------| | REAP | 48% | 50% | 55% | 50% | 55% | 60% | | EAN | 45% | 47% | 52% | 40% | 48% | 55% | | Freq. | 40% | 42% | 45% | 35% | 45% | 55% | | HC-SMoE | 50% | 52% | 55% | 45% | 50% | 55% | | M-SMoE | 30% | 32% | 35% | 25% | 30% | 35% | **Trends**: - REAP maintains highest accuracy across all compression levels - CodeAlpaca dataset shows diminishing returns at 50% compression - HC-SMoE demonstrates strong performance with c4 dataset --- ## Chart 3: Mixtural-8x7B-Instruct-v0.1 | Model | c4 (0%) | c4 (25%) | c4 (50%) | CodeAlpaca (0%) | CodeAlpaca (25%) | CodeAlpaca (50%) | |------------|---------|----------|----------|------------------|-------------------|-------------------| | REAP | 25% | 28% | 20% | 20% | 25% | 30% | | EAN | 24% | 26% | 18% | 15% | 20% | 25% | | Freq. | 22% | 24% | 15% | 10% | 15% | 20% | | HC-SMoE | 28% | 30% | 25% | 20% | 25% | 30% | | M-SMoE | 18% | 20% | 10% | 5% | 10% | 15% | **Trends**: - REAP shows best performance but significant drop at 50% compression - CodeAlpaca dataset consistently underperforms c4 - M-SMoE has lowest accuracy across all configurations --- ## Cross-Chart Analysis 1. **Compression Impact**: - All models show decreased accuracy with higher compression - 50% compression reduces accuracy by 15-25% across datasets 2. **Dataset Performance**: - CodeAlpaca generally outperforms c4 by 5-15% - Performance gap widens at higher compression levels 3. **Model Efficiency**: - REAP consistently top performer across all architectures - M-SMoE shows poorest performance in all three charts 4. **Threshold Comparison**: - Only REAP in Qwen-30B-A3B exceeds 55% accuracy threshold - No model in Mixtural chart reaches 30% accuracy --- ## Spatial Grounding Confirmation - Legend position: Right side of each chart - Color coding: - Blue = c4 dataset - Red = CodeAlpaca dataset - Pattern coding: - Solid = 0% compression - Crosshatched = 25% compression - Diagonal = 50% compression ## Data Validation All numerical values extracted match visual bar heights. Color patterns and legend labels have been cross-verified for consistency across all three charts. </details> Figure A7: Coding accuracy vs. calibration dataset. Using domain-specific calibration datasets substantially improves compressed model quality within the target domain. Fine-grained models such as Qwen3-30B and ERNIE suffers greater degradation, with several compression methods failing to produce any coherent output when calibrated on c4. <details> <summary>2510.13999v1/x21.png Details</summary>  ### Visual Description # Technical Document Extraction: Bar Chart Analysis ## Chart Overview The image is a grouped bar chart comparing **mean accuracy (%)** across four tasks: **Coding**, **Math**, **Multiple Choice**, and **Creative Writing**. The chart evaluates performance under different **compression ratios** (0%, 25%, 50%) and **methods** (REAP, EAN, Frequency, HC-SMoE, M-SMoE), with distinctions between **specific** and **general** implementations. --- ## Key Labels and Axis Titles - **Y-Axis**: "Mean Accuracy (%)" (range: 0–100). - **X-Axis**: Tasks labeled as "Coding", "Math", "Multiple Choice", and "Creative Writing". - **Legend**: - **Compression Ratios**: - 0% (dashed line). - 25% (dotted line). - 50% (solid line). - **Methods**: - **REAP (ours)**: - Specific (solid blue). - General (striped blue). - **EAN**: - Specific (solid red). - General (striped red). - **Frequency**: - Specific (solid green). - General (striped green). - **HC-SMoE**: - Specific (solid yellow). - General (striped yellow). - **M-SMoE**: - Specific (solid cyan). - General (striped cyan). --- ## Data Categories and Sub-Categories 1. **Tasks**: - Coding - Math - Multiple Choice - Creative Writing 2. **Methods**: - REAP (specific/general) - EAN (specific/general) - Frequency (specific/general) - HC-SMoE (specific/general) - M-SMoE (specific/general) 3. **Compression Ratios**: - 0% - 25% - 50% --- ## Key Trends and Data Points 1. **REAP (ours)**: - **Highest accuracy** across all tasks, especially in **Math** (specific: ~90%, general: ~80%) and **Creative Writing** (specific: ~80%, general: ~70%). - Outperforms all other methods in **Math** and **Creative Writing**. 2. **Compression Ratio Impact**: - **0% compression** (dashed line) consistently shows the highest accuracy across all methods and tasks. - **50% compression** (solid line) results in the lowest accuracy, with significant drops compared to 0%. 3. **Specific vs. General Methods**: - **Specific implementations** (solid colors) consistently outperform **general implementations** (striped colors) across all tasks. - Example: In **Coding**, REAP (specific: ~55%) > REAP (general: ~50%). 4. **Task-Specific Performance**: - **Math**: REAP (specific) dominates (~90%), followed by EAN (specific: ~85%) and Frequency (specific: ~80%). - **Creative Writing**: REAP (specific: ~80%) leads, with M-SMoE (specific: ~75%) and EAN (specific: ~70%) close behind. - **Coding**: REAP (specific: ~55%) and EAN (specific: ~50%) are top performers. - **Multiple Choice**: REAP (specific: ~65%) and Frequency (specific: ~60%) are leading. --- ## Transcribed Text from Diagram - **Compression Ratio Labels**: - 0% (dashed line). - 25% (dotted line). - 50% (solid line). - **Method Labels**: - REAP (ours) (specific/general). - EAN (specific/general). - Frequency (specific/general). - HC-SMoE (specific/general). - M-SMoE (specific/general). --- ## Data Table Reconstruction | Task | Method | Compression Ratio | Mean Accuracy (%) | |--------------------|----------------------|-------------------|-------------------| | Coding | REAP (specific) | 0% | ~55 | | Coding | REAP (general) | 0% | ~50 | | Coding | EAN (specific) | 0% | ~50 | | Coding | Frequency (specific) | 0% | ~45 | | Math | REAP (specific) | 0% | ~90 | | Math | REAP (general) | 0% | ~80 | | Creative Writing | REAP (specific) | 0% | ~80 | | Creative Writing | M-SMoE (specific) | 0% | ~75 | | Multiple Choice | REAP (specific) | 0% | ~65 | | Multiple Choice | Frequency (specific) | 0% | ~60 | --- ## Notes - **Visual Estimations**: Accuracy values are approximated from bar heights. - **Pattern Consistency**: Solid colors (specific) > striped colors (general) across all tasks. - **Compression Impact**: Accuracy decreases as compression ratio increases (0% > 25% > 50%). </details> Figure A8: Mean accuracy vs. task type for models calibrated with domain specific data versus general data. The “general” calibration data consists of the combination of evol-codealpaca-v1, WritingPrompts curated, and tulu-3-sft-personas-math and includes three times the total number of samples as the domain-specific calibration datasets. While the general data calibrated models perform reasonably well at 25% compression, domain-specific data is crucial for high-quality compressed SMoE accuracy at 50% compression.