Sparse Reward
Sparse reward reinforcement learning tackles the challenge of training agents in environments where positive feedback is infrequent, hindering efficient learning. Current research focuses on improving exploration strategies through techniques like optimistic Thompson sampling and intrinsic reward shaping, often employing deep deterministic policy gradients (DDPG), transformers, and generative flow networks (GFlowNets) to address the problem. These advancements aim to enhance sample efficiency and improve the performance of reinforcement learning agents in complex, real-world scenarios characterized by sparse rewards, such as robotics and multi-agent systems. The resulting improvements in sample efficiency and robustness have significant implications for various applications, including robotics, personalized recommendations, and human-AI collaboration.