# Convergence and Implicit Bias of Gradient Descent on Continual Linear Classification

arXiv: https://arxiv.org/abs/2504.12712 · HTML: https://mlsanity.com/paper/2504.12712/

## Key facts

- Cited by 9 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 17 Apr 2025.

## Built on by (most cited first, 9 of 9)

- [Fast Last-Iterate Convergence of SGD in the Smooth Interpolation Regime](https://mlsanity.com/paper/2507.11274/) (2025)
- [Optimal Rates in Continual Linear Regression via Increasing Regularization](https://mlsanity.com/paper/2506.06501/) (2025)
- [Putting a Face to Forgetting: Continual Learning meets Mechanistic Interpretability](https://mlsanity.com/paper/2601.22012/) (2026)
- [Interference and Retention in Continual Learning](https://mlsanity.com/paper/2607.09202/) (2026)
- [From Order to Distribution: An Exact Operator Framework for Forgetting in Continual Learning](https://mlsanity.com/paper/2604.13460/) (2026)
- [Convergence of Continual Learning in Homogeneous Deep Networks](https://mlsanity.com/paper/2606.30559/) (2026)
- [SingularClip: Preventing Spectral Collapse to Maintain Plasticity in Continual and Reinforcement Learning](https://mlsanity.com/paper/2608.18319/) (2026)
- [The Sequential Price of Continual Learning](https://mlsanity.com/paper/2609.29674/) (2026)
- [Ideal Paths for Approximating Logistic Gradient Descent Trajectories at Large Initialization](https://mlsanity.com/paper/2610.04142/) (2026)

## Abstract (arXiv)

We study continual learning on multiple linear classification tasks by sequentially running gradient descent (GD) for a fixed budget of iterations per task. When all tasks are jointly linearly separable and are presented in a cyclic/random order, we show the directional convergence of the trained linear classifier to the joint (offline) max-margin solution. This is surprising because GD training on a single task is implicitly biased towards the individual max-margin solution for the task, and the direction of the joint max-margin solution can be largely different from these individual solutions. Additionally, when tasks are given in a cyclic order, we present a non-asymptotic analysis on cycle-averaged forgetting, revealing that (1) alignment between tasks is indeed closely tied to catastrophic forgetting and backward knowledge transfer and (2) the amount of forgetting vanishes to zero as the cycle repeats. Lastly, we analyze the case where the tasks are no longer jointly separable and show that the model trained in a cyclic order converges to the unique minimum of the joint loss function.
