AI engineering glossary · Reinforcement learning
What is SARSA?
SARSA: An on-policy temporal-difference control method that updates action values using the quintuple state, action, reward, next state, next action. Formula: Q(s,a) = Q(s,a) + alpha*[r + gamma*Q(s',a') - Q(s,a)], where a' is the choice actually made next, including exploratory ones.
SARSA: an example
In a cliff-walking grid, SARSA learns a safer path away from the edge because it accounts for its own random slips.
Related terms
More Reinforcement learning terms
- Score function estimator
- Self-play
- Sim-to-real transfer
- Softmax exploration
- Sparse reward
- State
- Stochastic policy
- Target network
Where you learn it
SARSA is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.