Fairness-Regularized Online Optimization with Switching Costs

Pengfei Li; Yuelin Han; Adam Wierman; Shaolei Ren

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arXiv · 2512.11131

Fairness-Regularized Online Optimization with Switching Costs

Pengfei Li·Yuelin Han·Adam Wierman·Shaolei Ren

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Abstract

Fairness and action smoothness are two crucial considerations in many online optimization problems, but they have yet to be addressed simultaneously. In this paper, we study a new and challenging setting of fairness-regularized smoothed online convex optimization with switching costs. First, to highlight the fundamental challenges introduced by the long-term fairness regularizer evaluated based on the entire sequence of actions, we prove that even without switching costs, no online algorithms can possibly achieve a sublinear regret or finite competitive ratio compared to the offline optimal algorithm as the problem episode length $T$ increases. Then, we propose FairOBD (Fairness-regularized Online Balanced Descent), which reconciles the tension between minimizing the hitting cost, switching cost, and fairness cost. Concretely, FairOBD decomposes the long-term fairness cost into a sequence of online costs by introducing an auxiliary variable and then leverages the auxiliary variable to regularize the online actions for fair outcomes. Based on a new approach to account for switching costs, we prove that FairOBD offers a worst-case asymptotic competitive ratio against a novel benchmark -- the optimal offline algorithm with parameterized constraints -- by considering $T\to\infty$. Finally, we run trace-driven experiments of dynamic computing resource provisioning for socially responsible AI inference to empirically evaluate FairOBD, showing that FairOBD can effectively reduce the total fairness-regularized cost and better promote fair outcomes compared to existing baseline solutions.

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BibTeX RIS

Pengfei Li, Yuelin Han, Adam Wierman, Shaolei Ren. 2025-12-11. Fairness-Regularized Online Optimization with Switching Costs. https://arxiv.org/abs/2512.11131

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