# A General Theory for Softmax Gating Multinomial Logistic Mixture of Experts

arXiv: https://arxiv.org/abs/2310.14188 · HTML: https://mlsanity.com/paper/2310.14188/

## Key facts

- Cited by 23 papers in the map (data through 14 Oct 2026).
- Placed in MoE theory and gating functions, one of 12 directions in Mixture-of-experts.
- Builds on 28 of its 41 references that are in the map.
- First posted on arXiv 22 Oct 2023.

## Placed in

- Mixture-of-experts / [MoE theory and gating functions](https://mlsanity.com/moe/moe-theory-and-gating-functions/)

## Builds on (most cited first, 28 of 28)

- [An Image is Worth 16x16 Words: Transformers for Image Recognition at Scale](https://mlsanity.com/paper/2010.11929/) (2020)
- [Outrageously Large Neural Networks: The Sparsely-Gated Mixture-of-Experts Layer](https://mlsanity.com/paper/1701.06538/) (2017)
- [Switch Transformers: Scaling to Trillion Parameter Models with Simple and Efficient Sparsity](https://mlsanity.com/paper/2101.03961/) (2021)
- [Conformer: Convolution-augmented Transformer for Speech Recognition](https://mlsanity.com/paper/2005.08100/) (2020)
- [GShard: Scaling Giant Models with Conditional Computation and Automatic Sharding](https://mlsanity.com/paper/2006.16668/) (2020)
- [GLaM: Efficient Scaling of Language Models with Mixture-of-Experts](https://mlsanity.com/paper/2112.06905/) (2021)
- [Scaling Vision with Sparse Mixture of Experts](https://mlsanity.com/paper/2106.05974/) (2021)
- [Mixture-of-Experts with Expert Choice Routing](https://mlsanity.com/paper/2202.09368/) (2022)
- [VLMo: Unified Vision-Language Pre-Training with Mixture-of-Modality-Experts](https://mlsanity.com/paper/2111.02358/) (2021)
- [DSelect-k: Differentiable Selection in the Mixture of Experts with Applications to Multi-Task Learning](https://mlsanity.com/paper/2106.03760/) (2021)
- [M3ViT: Mixture-of-Experts Vision Transformer for Efficient Multi-task Learning with Model-Accelerator Co-design](https://mlsanity.com/paper/2210.14793/) (2022)
- [Sparsely Activated Mixture-of-Experts are Robust Multi-Task Learners](https://mlsanity.com/paper/2204.07689/) (2022)
- [Convergence Rates for Gaussian Mixtures of Experts](https://mlsanity.com/paper/1907.04377/) (2019)
- [Demystifying Softmax Gating Function in Gaussian Mixture of Experts](https://mlsanity.com/paper/2305.03288/) (2023)
- [Brainformers: Trading Simplicity for Efficiency](https://mlsanity.com/paper/2306.00008/) (2023)
- [EvoMoE: An Evolutional Mixture-of-Experts Training Framework via Dense-To-Sparse Gate](https://mlsanity.com/paper/2112.14397/) (2021)
- [Statistical Perspective of Top-K Sparse Softmax Gating Mixture of Experts](https://mlsanity.com/paper/2309.13850/) (2023)
- [EM Converges for a Mixture of Many Linear Regressions](https://mlsanity.com/paper/1905.12106/) (2019)
- [Probabilistic Mixture-of-Experts for Efficient Deep Reinforcement Learning](https://mlsanity.com/paper/2104.09122/) (2021)
- [SpeechMoE2: Mixture-of-Experts Model with Improved Routing](https://mlsanity.com/paper/2111.11831/) (2021)
- [Global Convergence of EM Algorithm for Mixtures of Two Component Linear Regression](https://mlsanity.com/paper/1810.05752/) (2018)
- [On the Minimax Optimality of the EM Algorithm for Learning Two-Component Mixed Linear Regression](https://mlsanity.com/paper/2006.02601/) (2020)
- [Refined Convergence Rates for Maximum Likelihood Estimation under Finite Mixture Models](https://mlsanity.com/paper/2202.08786/) (2022)
- [Towards Convergence Rates for Parameter Estimation in Gaussian-gated Mixture of Experts](https://mlsanity.com/paper/2305.07572/) (2023)
- [A Mixture-of-Expert Approach to RL-based Dialogue Management](https://mlsanity.com/paper/2206.00059/) (2022)
- [High-Dimensional Regression with Gaussian Mixtures and Partially-Latent Response Variables](https://mlsanity.com/paper/1308.2302/) (2013)
- [Regularized Estimation and Feature Selection in Mixtures of Generalized Linear Experts](https://mlsanity.com/paper/1907.06994/) (2019)
- [Functional mixture-of-experts for classification](https://mlsanity.com/paper/2202.13934/) (2022)

## Built on by (most cited first, 23 of 23)

- [A Comprehensive Survey of Mixture-of-Experts: Algorithms, Theory, and Applications](https://mlsanity.com/paper/2503.07137/) (2025)
- [FuseMoE: Mixture-of-Experts Transformers for Fleximodal Fusion](https://mlsanity.com/paper/2402.03226/) (2024)
- [Sigmoid Gating is More Sample Efficient than Softmax Gating in Mixture of Experts](https://mlsanity.com/paper/2405.13997/) (2024)
- [On Least Square Estimation in Softmax Gating Mixture of Experts](https://mlsanity.com/paper/2402.02952/) (2024)
- [Is Temperature Sample Efficient for Softmax Gaussian Mixture of Experts?](https://mlsanity.com/paper/2401.13875/) (2024)
- [RepLoRA: Reparameterizing Low-Rank Adaptation via the Perspective of Mixture of Experts](https://mlsanity.com/paper/2502.03044/) (2025)
- [Generalization Error Analysis for Sparse Mixture-of-Experts: A Preliminary Study](https://mlsanity.com/paper/2403.17404/) (2024)
- [On Zero-Initialized Attention: Optimal Prompt and Gating Factor Estimation](https://mlsanity.com/paper/2502.03029/) (2025)
- [Convergence Rates for Softmax Gating Mixture of Experts](https://mlsanity.com/paper/2503.03213/) (2025)
- [Sparsity is Combinatorial Depth: Quantifying MoE Expressivity via Tropical Geometry](https://mlsanity.com/paper/2602.03204/) (2026)
- [Sparse Mixture-of-Experts for Compositional Generalization: Empirical Evidence and Theoretical Foundations of Optimal Sparsity](https://mlsanity.com/paper/2410.13964/) (2024)
- [Guided by the Experts: Provable Feature Learning Dynamic of Soft-Routed Mixture-of-Experts](https://mlsanity.com/paper/2510.07205/) (2025)
- [Dendrograms of Mixing Measures for Softmax-Gated Gaussian Mixture of Experts: Consistency Without Model Sweeps](https://mlsanity.com/paper/2510.12744/) (2025)
- [On Minimax Estimation of Parameters in Softmax-Contaminated Mixture of Experts](https://mlsanity.com/paper/2505.18455/) (2025)
- [Robustness of Mixtures of Experts to Feature Noise](https://mlsanity.com/paper/2601.14792/) (2026)
- [A Statistical Theory of Gated Attention through the Lens of Hierarchical Mixture of Experts](https://mlsanity.com/paper/2602.01468/) (2026)
- [Soft-to-Hard Routing in Sparse Mixture-of-Experts Models](https://mlsanity.com/paper/2605.02124/) (2026)
- [Revisiting Incremental Stochastic Majorization-Minimization Algorithms with Applications to Mixture of Experts](https://mlsanity.com/paper/2601.19811/) (2026)
- [Improving Minimax Estimation Rates for Contaminated Mixture of Multinomial Logistic Experts via Expert Heterogeneity](https://mlsanity.com/paper/2602.00939/) (2026)
- [Rethinking Multinomial Logistic Mixture of Experts with Sigmoid Gating Function](https://mlsanity.com/paper/2602.01466/) (2026)
- [Fast Model Selection and Stable Optimization for Softmax-Gated Multinomial-Logistic Mixture of Experts Models](https://mlsanity.com/paper/2602.07997/) (2026)
- [Mixture-of-Experts in Remote Sensing: A Survey](https://mlsanity.com/paper/2604.03342/) (2026)
- [Structure Aware Neural Architecture Search for Mixture of Experts](https://mlsanity.com/paper/2608.29817/) (2026)

## Abstract (arXiv)

Mixture-of-experts (MoE) model incorporates the power of multiple submodels via gating functions to achieve greater performance in numerous regression and classification applications. From a theoretical perspective, while there have been previous attempts to comprehend the behavior of that model under the regression settings through the convergence analysis of maximum likelihood estimation in the Gaussian MoE model, such analysis under the setting of a classification problem has remained missing in the literature. We close this gap by establishing the convergence rates of density estimation and parameter estimation in the softmax gating multinomial logistic MoE model. Notably, when part of the expert parameters vanish, these rates are shown to be slower than polynomial rates owing to an inherent interaction between the softmax gating and expert functions via partial differential equations. To address this issue, we propose using a novel class of modified softmax gating functions which transform the input before delivering them to the gating functions. As a result, the previous interaction disappears and the parameter estimation rates are significantly improved.