We study learning algorithms that seek to minimize the conditional value-at-risk (CVaR), when all the learner knows is that the losses incurred may be heavy-tailed. We begin by studying a general-purpose estimator of CVaR for potentially heavy-tailed random variables, which is easy to implement in practice, and requires nothing more than finite variance and a distribution function that does not change too fast or slow around just the quantile of interest. With this estimator in hand, we then derive a new learning algorithm which robustly chooses among candidates produced by stochastic gradient-driven sub-processes. For this procedure we provide high-probability excess CVaR bounds, and to complement the theory we conduct empirical tests of the underlying CVaR estimator and the learning algorithm derived from it.
Stabilized Maximum-Likelihood Iterative Quantum Amplitude Estimation for Structural CVaR under Correlated Random Fields
Department of Mechanical Engineering(机械工程系);Engineering Science, The University of North Carolina at Charlotte, Charlotte, NC 28223, USA(工程科学,北卡罗来纳大学夏洛特分校);School of Data Science, The University of North Carolina at Charlotte, Charlotte, NC 28223, USA(数据科学学院)
On the Generalization and Robustness in Conditional Value-at-Risk
Dept. of Mathematics IISER, Pune(数学系,印度科学研究所,普恩);Dept. of Computer Science and Automation Indian Institute of Sciecne, Bangalore(计算机科学与自动化系,印度科学研究院,班加罗尔);The Alan Turing Institute Greater London, England, UK(艾伦·图灵研究所,伦敦,英格兰,英国)
LTCI, Télécom Paris, Institut Polytechnique de Paris(巴黎电信学院,巴黎理工学院);Université Paris Cité, Université Paris Saclay, ENS Paris Saclay, CNRS, SSA, INSERM, Centre Borelli(巴黎西岱大学,巴黎萨克雷大学,巴黎高等师范学校巴黎萨克雷分校,法国国家科学研究中心,SSA,INSERM,博尔莱中心)