Skip to main content
Back to Glossary
Techniques

Reinforcement Learning

A machine learning approach where agents learn optimal behavior through trial and error, receiving rewards or penalties for their actions.


Learning Through Experience

Reinforcement learning works like training a dog. You don't show the dog exactly what to do step by step. Instead, you reward good behavior and discourage bad behavior. Over time, the dog learns what actions lead to treats.

In RL, an agent takes actions in an environment, observes what happens, and receives rewards or penalties. The goal is to learn a policy - a strategy for choosing actions that maximizes long-term rewards. This makes RL perfect for problems where you know what success looks like but not how to achieve it.

Why Reinforcement Learning Is Different

Unlike supervised learning, RL doesn't need labeled examples of correct behavior. The agent discovers good strategies through exploration. Unlike unsupervised learning, there's a clear objective - maximize reward. This creates a unique learning dynamic.

RL systems famously learned to play Atari games better than humans, beat world champions at Go and chess, and control robots to perform complex tasks. They've also shown promise in areas like recommendation systems, trading algorithms, and resource management.

The tricky part is designing reward functions that actually lead to desired behavior. RL agents are excellent at finding loopholes - achieving high rewards in unintended ways. Getting the incentives right is both an art and a science.

Related Terms

More in Techniques