# Dealing with Sparse Rewards in Reinforcement Learning

arXiv: https://arxiv.org/abs/1910.09281 · HTML: https://mlsanity.com/paper/1910.09281/

## Key facts

- Cited by 42 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 21 Oct 2019.

## Built on by (most cited first, 30 of 42)

- [Neural Combinatorial Optimization with Heavy Decoder: Toward Large Scale Generalization](https://mlsanity.com/paper/2310.07985/) (2023)
- [A Survey on Self-Evolution of Large Language Models](https://mlsanity.com/paper/2404.14387/) (2024)
- [Code as Reward: Empowering Reinforcement Learning with VLMs](https://mlsanity.com/paper/2402.04764/) (2024)
- [Towards Better Alignment: Training Diffusion Models with Reinforcement Learning Against Sparse Rewards](https://mlsanity.com/paper/2503.11240/) (2025)
- [ScheduleNet: Learn to solve multi-agent scheduling problems with reinforcement learning](https://mlsanity.com/paper/2106.03051/) (2021)
- [Fine-Grained GRPO for Precise Preference Alignment in Flow Models](https://mlsanity.com/paper/2510.01982/) (2025)
- [Behavior Alignment via Reward Function Optimization](https://mlsanity.com/paper/2310.19007/) (2023)
- [SCAR: Shapley Credit Assignment for More Efficient RLHF](https://mlsanity.com/paper/2505.20417/) (2025)
- [Exploratory Optimal Stopping: A Singular Control Formulation](https://mlsanity.com/paper/2408.09335/) (2024)
- [Efficient Diversity-based Experience Replay for Deep Reinforcement Learning](https://mlsanity.com/paper/2410.20487/) (2024)
- [Do Less, Achieve More: Do We Need Every-Step Optimization for RL Fine-tuning of Diffusion Models?](https://mlsanity.com/paper/2605.15855/) (2026)
- [A Reinforcement Learning Approach to Parameter Selection for Distributed Optimal Power Flow](https://mlsanity.com/paper/2110.11991/) (2021)
- [Discovering and Exploiting Sparse Rewards in a Learned Behavior Space](https://mlsanity.com/paper/2111.01919/) (2021)
- [Learning to Disprove: Formal Counterexample Generation with Large Language Models](https://mlsanity.com/paper/2603.19514/) (2026)
- [Collaborative Training of Heterogeneous Reinforcement Learning Agents in Environments with Sparse Rewards: What and When to Share?](https://mlsanity.com/paper/2202.12174/) (2022)
- [Take a Step and Reconsider: Sequence Decoding for Self-Improved Neural Combinatorial Optimization](https://mlsanity.com/paper/2407.17206/) (2024)
- [Automated Rewards via LLM-Generated Progress Functions](https://mlsanity.com/paper/2410.09187/) (2024)
- [Goal-constrained Sparse Reinforcement Learning for End-to-End Driving](https://mlsanity.com/paper/2103.09189/) (2021)
- [Feasibility Consistent Representation Learning for Safe Reinforcement Learning](https://mlsanity.com/paper/2405.11718/) (2024)
- [From Sparse to Dense: Toddler-inspired Reward Transition in Goal-Oriented Reinforcement Learning](https://mlsanity.com/paper/2501.17842/) (2025)
- [VARD: Efficient and Dense Fine-Tuning for Diffusion Models with Value-based RL](https://mlsanity.com/paper/2505.15791/) (2025)
- [Collaborative Route Planning of UAVs, Workers and Cars for Crowdsensing in Disaster Response](https://mlsanity.com/paper/2308.11088/) (2023)
- [Learning Gait-Aware Quadruped Locomotion with Temporal Logic Specifications](https://mlsanity.com/paper/2607.00442/) (2026)
- [WILD-SCAV: Benchmarking FPS Gaming AI on Unity3D-based Environments](https://mlsanity.com/paper/2210.09026/) (2022)
- [Diversity is Strength: Mastering Football Full Game with Interactive Reinforcement Learning of Multiple AIs](https://mlsanity.com/paper/2306.15903/) (2023)
- [On shallow planning under partial observability](https://mlsanity.com/paper/2407.15820/) (2024)
- [World Models as an Intermediary between Agents and the Real World](https://mlsanity.com/paper/2602.00785/) (2026)
- [STAIR: Effective Incident Response Using an End-to-End Agentic Planning Framework](https://mlsanity.com/paper/2608.09524/) (2026)
- [Deep Reinforcement Learning for mmWave Initial Beam Alignment](https://mlsanity.com/paper/2302.08969/) (2023)
- [Confidence-Controlled Exploration: Efficient Sparse-Reward Policy Learning for Robot Navigation](https://mlsanity.com/paper/2306.06192/) (2023)

## Abstract (arXiv)

Successfully navigating a complex environment to obtain a desired outcome is a difficult task, that up to recently was believed to be capable only by humans. This perception has been broken down over time, especially with the introduction of deep reinforcement learning, which has greatly increased the difficulty of tasks that can be automated. However, for traditional reinforcement learning agents this requires an environment to be able to provide frequent extrinsic rewards, which are not known or accessible for many real-world environments. This project aims to explore and contrast existing reinforcement learning solutions that circumnavigate the difficulties of an environment that provide sparse rewards. Different reinforcement solutions will be implemented over a several video game environments with varying difficulty and varying frequency of rewards, as to properly investigate the applicability of these solutions. This project introduces a novel reinforcement learning solution by combining aspects of two existing state of the art sparse reward solutions, curiosity driven exploration and unsupervised auxiliary tasks.
