# UGAE: A Novel Approach to Non-exponential Discounting

arXiv: https://arxiv.org/abs/2302.05740 · HTML: https://mlsanity.com/paper/2302.05740/

## Key facts

- Cited by 3 papers in the map (data through 14 Oct 2026).
- Builds on 12 of its 31 references that are in the map.
- First posted on arXiv 11 Feb 2023.

## Builds on (most cited first, 12 of 12)

- [Adam: A Method for Stochastic Optimization](https://mlsanity.com/paper/1412.6980/) (2014)
- [Proximal Policy Optimization Algorithms](https://mlsanity.com/paper/1707.06347/) (2017)
- [Trust Region Policy Optimization](https://mlsanity.com/paper/1502.05477/) (2015)
- [Asynchronous Methods for Deep Reinforcement Learning](https://mlsanity.com/paper/1602.01783/) (2016)
- [High-Dimensional Continuous Control Using Generalized Advantage Estimation](https://mlsanity.com/paper/1506.02438/) (2015)
- [OpenAI Gym](https://mlsanity.com/paper/1606.01540/) (2016)
- [Hyperbolic Discounting and Learning over Multiple Horizons](https://mlsanity.com/paper/1902.06865/) (2019)
- [Learning Fair Policies in Multiobjective (Deep) Reinforcement Learning with Average and Discounted Rewards](https://mlsanity.com/paper/2008.07773/) (2020)
- [Discount Factor as a Regularizer in Reinforcement Learning](https://mlsanity.com/paper/2007.02040/) (2020)
- [Rethinking the Discount Factor in Reinforcement Learning: A Decision Theoretic Approach](https://mlsanity.com/paper/1902.02893/) (2019)
- [Reinforcement Learning with Non-Exponential Discounting](https://mlsanity.com/paper/2209.13413/) (2022)
- [Understanding reinforcement learned crowds](https://mlsanity.com/paper/2209.09344/) (2022)

## Built on by (most cited first, 3 of 3)

- [Reward Function Design for Crowd Simulation via Reinforcement Learning](https://mlsanity.com/paper/2309.12841/) (2023)
- [medR: Reward Engineering for Clinical Offline Reinforcement Learning via Tri-Drive Potential Functions](https://mlsanity.com/paper/2602.03305/) (2026)
- [Beyond the Bellman Recursion: A Pontryagin-Guided Framework for Non-Exponential Discounting](https://mlsanity.com/paper/2605.20996/) (2026)

## Abstract (arXiv)

The discounting mechanism in Reinforcement Learning determines the relative importance of future and present rewards. While exponential discounting is widely used in practice, non-exponential discounting methods that align with human behavior are often desirable for creating human-like agents. However, non-exponential discounting methods cannot be directly applied in modern on-policy actor-critic algorithms. To address this issue, we propose Universal Generalized Advantage Estimation (UGAE), which allows for the computation of GAE advantage values with arbitrary discounting. Additionally, we introduce Beta-weighted discounting, a continuous interpolation between exponential and hyperbolic discounting, to increase flexibility in choosing a discounting method. To showcase the utility of UGAE, we provide an analysis of the properties of various discounting methods. We also show experimentally that agents with non-exponential discounting trained via UGAE outperform variants trained with Monte Carlo advantage estimation. Through analysis of various discounting methods and experiments, we demonstrate the superior performance of UGAE with Beta-weighted discounting over the Monte Carlo baseline on standard RL benchmarks. UGAE is simple and easily integrated into any advantage-based algorithm as a replacement for the standard recursive GAE.
