# Robust Risk-Sensitive Reinforcement Learning with Conditional Value-at-Risk

arXiv: https://arxiv.org/abs/2405.01718 · HTML: https://mlsanity.com/paper/2405.01718/

## Key facts

- Cited by 2 papers in the map (data through 14 Oct 2026).
- Placed in RL theory and sample complexity, one of 15 directions in Deep reinforcement learning methods.
- Builds on 16 of its 38 references that are in the map.
- First posted on arXiv 2 May 2024.

## Placed in

- Deep reinforcement learning methods / [RL theory and sample complexity](https://mlsanity.com/deeprl/rl-theory-and-sample-complexity/)

## Builds on (most cited first, 16 of 16)

- [Risk-Constrained Reinforcement Learning with Percentile Risk Criteria](https://mlsanity.com/paper/1512.01629/) (2015)
- [Risk-Sensitive and Robust Decision-Making: a CVaR Optimization Approach](https://mlsanity.com/paper/1506.02188/) (2015)
- [Risk-sensitive Reinforcement Learning](https://mlsanity.com/paper/1311.2097/) (2013)
- [Optimizing the CVaR via Sampling](https://mlsanity.com/paper/1404.3862/) (2014)
- [Algorithms for CVaR Optimization in MDPs](https://mlsanity.com/paper/1406.3339/) (2014)
- [Online Robust Reinforcement Learning with Model Uncertainty](https://mlsanity.com/paper/2109.14523/) (2021)
- [Being Optimistic to Be Conservative: Quickly Learning a CVaR Policy](https://mlsanity.com/paper/1911.01546/) (2019)
- [Efficient Risk-Averse Reinforcement Learning](https://mlsanity.com/paper/2205.05138/) (2022)
- [Towards Safe Reinforcement Learning via Constraining Conditional Value-at-Risk](https://mlsanity.com/paper/2206.04436/) (2022)
- [Near-Minimax-Optimal Risk-Sensitive Reinforcement Learning with CVaR](https://mlsanity.com/paper/2302.03201/) (2023)
- [Policy Gradients for CVaR-Constrained MDPs](https://mlsanity.com/paper/1405.2690/) (2014)
- [On the Dual Representation of Coherent Risk Measures](https://mlsanity.com/paper/1502.06155/) (2015)
- [Distributionally Robust Optimization with Decision Dependent Ambiguity Sets](https://mlsanity.com/paper/1806.09215/) (2018)
- [TRC: Trust Region Conditional Value at Risk for Safe Reinforcement Learning](https://mlsanity.com/paper/2312.00344/) (2023)
- [Optimization under Decision-Dependent Uncertainty](https://mlsanity.com/paper/1611.07992/) (2016)
- [The f-Divergence Reinforcement Learning Framework](https://mlsanity.com/paper/2109.11867/) (2021)

## Built on by (most cited first, 2 of 2)

- [Robust Offline Reinforcement Learning for Non-Markovian Decision Processes](https://mlsanity.com/paper/2411.07514/) (2024)
- [Robust Risk-Sensitive Reinforcement Learning from Corrupted Human Feedback](https://mlsanity.com/paper/2609.38938/) (2026)

## Abstract (arXiv)

Robust Markov Decision Processes (RMDPs) have received significant research interest, offering an alternative to standard Markov Decision Processes (MDPs) that often assume fixed transition probabilities. RMDPs address this by optimizing for the worst-case scenarios within ambiguity sets. While earlier studies on RMDPs have largely centered on risk-neutral reinforcement learning (RL), with the goal of minimizing expected total discounted costs, in this paper, we analyze the robustness of CVaR-based risk-sensitive RL under RMDP. Firstly, we consider predetermined ambiguity sets. Based on the coherency of CVaR, we establish a connection between robustness and risk sensitivity, thus, techniques in risk-sensitive RL can be adopted to solve the proposed problem. Furthermore, motivated by the existence of decision-dependent uncertainty in real-world problems, we study problems with state-action-dependent ambiguity sets. To solve this, we define a new risk measure named NCVaR and build the equivalence of NCVaR optimization and robust CVaR optimization. We further propose value iteration algorithms and validate our approach in simulation experiments.
