Build the agent-environment mental model and learn how states, observations, actions, rewards, returns, and policies fit together in sequential decision making.
Tutorials
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That single distinction separates reinforcement learning from every other branch of machine learning—and it explains why these systems learn the way they…
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A reward is not a delayed label. That single confusion sits behind most of the trouble beginners have telling supervised learning and reinforcement…
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The agent never acts on the world. It acts on a report about the world—and that report is often incomplete, noisy, or misleading. Understanding the gap…
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A reward is feedback. The return is the scoreboard. Beginners often treat them as the same thing—and then wonder why their agent grabs the pebble instead…
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A policy is not a rulebook. It is a decision rule that keeps producing choices as the agent moves through the world—and every choice reshapes which futures…
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You're halfway through a tutorial when a sentence stops you cold: "The agent updates its Q-value using the discounted return from the trajectory." You know…
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Imagine you are playing a card game against an opponent. You can see your own hand perfectly, but your opponent's cards are hidden. You watch them draw,…
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You can follow the agent-environment loop: the agent sees a state, picks an action, gets a reward, and lands in a new state. Then it happens again. And…
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You don't need a math degree to start reinforcement learning. You need a small, ordered set of concepts—and each one arrives just when the RL idea that…
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