# Infinite-Dimensional Operator/Block Kaczmarz Algorithms: Regret Bounds and λ-Effectiveness

arXiv: https://arxiv.org/abs/2511.07604 · HTML: https://mlsanity.com/paper/2511.07604/

## Key facts

- Cited by 2 papers in the map (data through 14 Oct 2026).
- Builds on 14 of its 56 references that are in the map.
- First posted on arXiv 10 Nov 2025.

## Builds on (most cited first, 14 of 14)

- [Introduction to Online Convex Optimization](https://mlsanity.com/paper/1909.05207/) (2019)
- [A Tutorial on Thompson Sampling](https://mlsanity.com/paper/1707.02038/) (2017)
- [Stochastic Gradient Descent, Weighted Sampling, and the Randomized Kaczmarz algorithm](https://mlsanity.com/paper/1310.5715/) (2013)
- [How catastrophic can catastrophic forgetting be in linear regression?](https://mlsanity.com/paper/2205.09588/) (2022)
- [Unconstrained Online Linear Learning in Hilbert Spaces: Minimax Algorithms and Normal Approximations](https://mlsanity.com/paper/1403.0628/) (2014)
- [Online Linear Programming: Dual Convergence, New Algorithms, and Regret Bounds](https://mlsanity.com/paper/1909.05499/) (2019)
- [Regret Bounds for Reinforcement Learning via Markov Chain Concentration](https://mlsanity.com/paper/1808.01813/) (2018)
- [Bridging Distributional and Risk-sensitive Reinforcement Learning with Provable Regret Bounds](https://mlsanity.com/paper/2210.14051/) (2022)
- [Linear Partial Monitoring for Sequential Decision-Making: Algorithms, Regret Bounds and Applications](https://mlsanity.com/paper/2302.03683/) (2023)
- [Tight Regret Bounds for Noisy Optimization of a Brownian Motion](https://mlsanity.com/paper/2001.09327/) (2020)
- [Improved Regret Bounds for Bandits with Expert Advice](https://mlsanity.com/paper/2406.16802/) (2024)
- [Unconstrained Robust Online Convex Optimization](https://mlsanity.com/paper/2506.12781/) (2025)
- [A Kaczmarz algorithm for sequences of projections, infinite products, and applications to frames in IFS L2 spaces](https://mlsanity.com/paper/1904.04414/) (2019)
- [A Kaczmarz Algorithm for Solving Tree Based Distributed Systems of Equations](https://mlsanity.com/paper/1904.05732/) (2019)

## Built on by (most cited first, 2 of 2)

- [Use of operator defect identities in multi-channel signal plus residual-analysis via iterated products and telescoping energy-residuals: Applications to kernels in machine learning](https://mlsanity.com/paper/2601.18080/) (2026)
- [The role of parameter Jacobians in the stability of network outputs](https://mlsanity.com/paper/2608.27748/) (2026)

## Abstract (arXiv)

We present a variety of projection-based linear regression algorithms with a focus on modern machine-learning models and their algorithmic performance. We study the role of the relaxation parameter in generalized Kaczmarz algorithms and establish a priori regret bounds with explicit λ-dependence to quantify how much an algorithm's performance deviates from its optimal performance. A detailed analysis of relaxation parameter is also provided. Applications include: explicit regret bounds for the framework of Kaczmarz algorithm models, non-orthogonal Fourier expansions, and the use of regret estimates in modern machine learning models, including for noisy data, i.e., regret bounds for the noisy Kaczmarz algorithms. Motivated by machine-learning practice, our wider framework treats bounded operators (on infinite-dimensional Hilbert spaces), with updates realized as (block) Kaczmarz algorithms, leading to new and versatile results.
