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arXiv · 2609.29887

Cost-Sensitive Online Window Size Selection for Portfolio Management

Yi-Chen Liu·Chung-Han Hsieh
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Abstract

This paper investigates cost-sensitive online window size selection for portfolio management under changing market conditions. Specifically, we propose a two-level framework that constructs portfolios using candidate window sizes and dynamically aggregates them through online learning. By treating candidate window sizes as ``experts,'' we dynamically update their aggregation weights using turnover-inclusive losses. Moreover, we derive finite-horizon cost-sensitive tracking-regret bounds that account for turnover of the aggregated portfolio, with static regret as a special case. Under bounded losses and cost rates, suitably tuned Fixed Share achieves asymptotically no tracking regret for sublinear switching budgets, with Hedge covering the static case.

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Yi-Chen Liu, Chung-Han Hsieh. 2026-09-24. Cost-Sensitive Online Window Size Selection for Portfolio Management. https://arxiv.org/abs/2609.29887

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