](https://deep-paper.org/en/papers/2025-10/2004.07219/images/cover.png)
Beyond Online Training: Introducing D4RL for Real-World Offline Reinforcement Learning
The past decade has shown us the incredible power of large datasets. From ImageNet fueling the computer vision revolution to massive text corpora enabling models like GPT, it’s clear: data is the lifeblood of modern machine learning. Yet one of the most exciting fields—Reinforcement Learning (RL)—has largely been excluded from this data-driven paradigm. Traditionally, RL agents learn through active, online interaction with an environment—playing games, controlling robots, simulating trades—building policies through trial and error. This approach is powerful but often impractical, expensive, or dangerous in real-world contexts. We can’t let a self-driving car “explore” by crashing thousands of times or experiment recklessly in healthcare. ...