# Stability and Generalization of Straight-Through Estimators for Training Two-Layer Quantized Neural Networks

arXiv: https://arxiv.org/abs/2609.06430 · HTML: https://mlsanity.com/paper/2609.06430/

## Key facts

- No citing papers in the map yet (data through 14 Oct 2026).
- Builds on 16 of its 29 references that are in the map.
- First posted on arXiv 6 Sep 2026.

## Builds on (most cited first, 16 of 16)

- [Attention Is All You Need](https://mlsanity.com/paper/1706.03762/) (2017)
- [Deep Residual Learning for Image Recognition](https://mlsanity.com/paper/1512.03385/) (2015)
- [Estimating or Propagating Gradients Through Stochastic Neurons for Conditional Computation](https://mlsanity.com/paper/1308.3432/) (2013)
- [XNOR-Net: ImageNet Classification Using Binary Convolutional Neural Networks](https://mlsanity.com/paper/1603.05279/) (2016)
- [DoReFa-Net: Training Low Bitwidth Convolutional Neural Networks with Low Bitwidth Gradients](https://mlsanity.com/paper/1606.06160/) (2016)
- [Train faster, generalize better: Stability of stochastic gradient descent](https://mlsanity.com/paper/1509.01240/) (2015)
- [Understanding Straight-Through Estimator in Training Activation Quantized Neural Nets](https://mlsanity.com/paper/1903.05662/) (2019)
- [Training Deep Neural Networks with 8-bit Floating Point Numbers](https://mlsanity.com/paper/1812.08011/) (2018)
- [Fine-Grained Analysis of Stability and Generalization for Stochastic Gradient Descent](https://mlsanity.com/paper/2006.08157/) (2020)
- [ProxQuant: Quantized Neural Networks via Proximal Operators](https://mlsanity.com/paper/1810.00861/) (2018)
- [Stable Sample Compression Schemes: New Applications and an Optimal SVM Margin Bound](https://mlsanity.com/paper/2011.04586/) (2020)
- [Mirror Descent View for Neural Network Quantization](https://mlsanity.com/paper/1910.08237/) (2019)
- [Reintroducing Straight-Through Estimators as Principled Methods for Stochastic Binary Networks](https://mlsanity.com/paper/2006.06880/) (2020)
- [Demystifying and Generalizing BinaryConnect](https://mlsanity.com/paper/2110.13220/) (2021)
- [Learning Quantized Neural Nets by Coarse Gradient Method for Non-linear Classification](https://mlsanity.com/paper/2011.11256/) (2020)
- [Beyond Discreteness: Sample Complexity Analysis of Straight-Through Estimator for 1-bit Quantization](https://mlsanity.com/paper/2505.18113/) (2025)

## Abstract (arXiv)

We study the identity straight-through estimator (STE) for training a two-layer binary-activation network with hinge loss from the perspective of Statistical Learning Theory (SLT). Our central question is whether algorithmic stability can explain the statistical generalization of the estimator produced by the discontinuous STE training rule. In the saturated-output regime, the zero-initialized samplewise STE recursion is exactly the stochastic subgradient descent on the convex latent loss (-yu^top x)_+. This representation makes a stability analysis possible. We derive an exact distance identity for two coupled updates and prove approximate non-expansiveness of the common-example map, with a quadratic defect only when the two latent margins straddle zero. We then obtain explicit ℓ2 on-average model-stability and generalization bounds, transferring stability isometrically from the latent vector to the full first-layer matrix. Combining stability with a standard optimization bound yields an explicit excess induced-risk guarantee and the rate O(n-1/2) when T=n2. Under margin separability, a complementary argument gives the optimal-order O(R2/(γ2n)) expected excess misclassification error for a randomized one-pass STE iterate and a corresponding majority-vote bound.
