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arXiv · 2507.09444

Norms Based on Generalized Expected-Shortfalls and Applications

Shuyu Gong·Taizhong Hu·Zhenfeng Zou
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Abstract

This paper proposes a novel class of generalized Expected-Shortfall (ES) norms constructed via distortion risk measures, establishing a unified analytical framework for risk quantification. The proposed norms extend conventional ES methodology by incorporating flexible distortion functions. Specifically, we develop the mathematical duality theory for generalized-ES norms to support portfolio optimization tasks, while demonstrating their practical utility through projection problem solutions. The generalizedES norms are also applied to detect anomalies of financial time series data.

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Shuyu Gong, Taizhong Hu, Zhenfeng Zou. 2025-07-13. Norms Based on Generalized Expected-Shortfalls and Applications. https://arxiv.org/abs/2507.09444

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