# AdaGamma: State-Dependent Discounting for Temporal Adaptation in Reinforcement Learning

arXiv: https://arxiv.org/abs/2605.06149 · HTML: https://mlsanity.com/paper/2605.06149/

## Key facts

- Cited by 1 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 14 of its 25 references that are in the map.
- First posted on arXiv 7 May 2026.

## 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, 14 of 14)

- [Proximal Policy Optimization Algorithms](https://mlsanity.com/paper/1707.06347/) (2017)
- [Soft Actor-Critic: Off-Policy Maximum Entropy Deep Reinforcement Learning with a Stochastic Actor](https://mlsanity.com/paper/1801.01290/) (2018)
- [Continuous control with deep reinforcement learning](https://mlsanity.com/paper/1509.02971/) (2015)
- [Addressing Function Approximation Error in Actor-Critic Methods](https://mlsanity.com/paper/1802.09477/) (2018)
- [The Option-Critic Architecture](https://mlsanity.com/paper/1609.05140/) (2016)
- [Safety-Gymnasium: A Unified Safe Reinforcement Learning Benchmark](https://mlsanity.com/paper/2310.12567/) (2023)
- [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)
- [How to Discount Deep Reinforcement Learning: Towards New Dynamic Strategies](https://mlsanity.com/paper/1512.02011/) (2015)
- [Discounted Reinforcement Learning Is Not an Optimization Problem](https://mlsanity.com/paper/1910.02140/) (2019)
- [The Termination Critic](https://mlsanity.com/paper/1902.09996/) (2019)
- [On the Role of Discount Factor in Offline Reinforcement Learning](https://mlsanity.com/paper/2206.03383/) (2022)
- [Offline Reinforcement Learning: Role of State Aggregation and Trajectory Data](https://mlsanity.com/paper/2403.17091/) (2024)
- [A Tale of Sampling and Estimation in Discounted Reinforcement Learning](https://mlsanity.com/paper/2304.05073/) (2023)

## Built on by (most cited first, 1 of 1)

- [Let Credit Follow Computation: Architecture-Aware Credit Transport for Large Language Model Reinforcement Learning](https://mlsanity.com/paper/2608.21501/) (2026)

## Abstract (arXiv)

The discount factor in reinforcement learning controls both the effective planning horizon and the strength of bootstrapping, yet most deep RL methods use a single fixed value across all states. State-dependent discounting is a natural way to adapt temporal credit assignment to local state structure, but naively learning a discount function inside deep actor--critic methods creates a self-referential target: the learned discount scales the same bootstrap term against which it is trained. Consequently, TD-error-based objectives can admit a degenerate shortcut, reducing target dependence on downstream value estimates instead of learning meaningful temporal structure. We propose AdaGamma, a practical framework for state-dependent discounting in deep actor--critic reinforcement learning. AdaGamma learns a bounded discount function (γφ(s)) and trains it using a return-consistency objective that matches a one-step adaptive bootstrap to a multi-step return computed with a lagged, stop-gradient reference discount. This removes the direct target manipulation path and encourages the discount to encode state-dependent value propagation. We analyze the Bellman operator induced by a fixed state-dependent discount in finite tabular MDPs, proving contraction, exact soft policy iteration, and Lipschitz sensitivity under standard boundedness assumptions. Empirically, AdaGamma integrates into SAC and PPO, avoids TD-collapse, improves continuous-control benchmarks, and achieves statistically significant gains in a four-week online A/B test on the JD Logistics platform.
