Optimization of utility-based shortfall risk: A non-asymptotic viewpoint
- URL: http://arxiv.org/abs/2310.18743v2
- Date: Sat, 30 Mar 2024 08:53:49 GMT
- Title: Optimization of utility-based shortfall risk: A non-asymptotic viewpoint
- Authors: Sumedh Gupte, Prashanth L. A., Sanjay P. Bhat,
- Abstract summary: We consider the problems of estimation and optimization of utility-based shortfall risk (UBSR)
In the context of UBSR estimation, we derive a non-asymptotic bound on the mean-squared error of the classical sample average approximation (SAA) of UBSR.
We derive non-asymptotic bounds that quantify the rate of the gradient algorithm for UBSR optimization.
- Score: 11.907026010541674
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We consider the problems of estimation and optimization of utility-based shortfall risk (UBSR), which is a popular risk measure in finance. In the context of UBSR estimation, we derive a non-asymptotic bound on the mean-squared error of the classical sample average approximation (SAA) of UBSR. Next, in the context of UBSR optimization, we derive an expression for the UBSR gradient under a smooth parameterization. This expression is a ratio of expectations, both of which involve the UBSR. We use SAA for the numerator as well as denominator in the UBSR gradient expression to arrive at a biased gradient estimator. We derive non-asymptotic bounds on the estimation error, which show that our gradient estimator is asymptotically unbiased. We incorporate the aforementioned gradient estimator into a stochastic gradient (SG) algorithm for UBSR optimization. Finally, we derive non-asymptotic bounds that quantify the rate of convergence of our SG algorithm for UBSR optimization.
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