Study Reinforcement Learning

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everything, in one place

Library

Every lecture, exercise, homework set, cheat sheet, diagram, and reading list, in one place.

Everything in the study repo, on one page. Lectures are grouped by track, in the order the curriculum suggests.

Tracks

  1. Foundations: MDPs, value functions, policy gradients, actor-critic, trust regions, PPO. Every other track builds on these.
  2. Classical RL: The environment gives the reward. Off-policy and model-based methods, exploration, multi-agent RL, world models, meta-RL, robotics.
  3. RLHF: People compare two outputs, a reward model learns from the comparisons, and PPO, DPO, and their relatives optimize against it.
  4. RLAIF: An LLM judge or a written constitution stands in for the human labeler.
  5. RLVR and reasoning: A checker decides: the answer matches, the tests pass. Reasoning models, process vs outcome rewards, and how verifiers get gamed.
  6. Agentic RL: Multi-step tasks with tools, browsers, and code. The reward usually arrives at the end, so credit assignment gets hard.
  7. Offline RL: Learning from a fixed dataset with no new interaction, including imitation and distillation.
  8. Systems: How LLM-RL training runs: distributed rollouts and learners, inference engines, hardware.

Lectures

Foundations

Classical RL

RLHF

RLAIF

RLVR and reasoning

Agentic RL

Offline RL

Systems

Exercises

  • 01-mdps: value iteration on a gridworld (with lecture 01)
  • 02-policy-gradients: REINFORCE, solve CartPole (with lecture 02)
  • 03-q-learning: tabular Q-learning on FrozenLake (with lecture 03)
  • 04-actor-critic: actor-critic with a learned baseline, on CartPole (with lecture 04)
  • 05-ppo: PPO with GAE, solve CartPole (with lecture 06)
  • 09-reward-model: Bradley-Terry reward model on synthetic preferences (with lecture 09)
  • 11-dpo: DPO on a toy preference dataset (with lecture 11)
  • 15-grpo-rlvr: GRPO on a verifiable arithmetic toy task (with lecture 15)
  • 20-exploration: RND on a sparse-reward chain MDP (with lecture 20)

Homework

Cheat sheets

Diagrams

Reading lists

Notes from 2017

Videos, the plan, and the repo