A learning agent balances trying unfamiliar actions with repeating ones that have worked. Its regret is the performance gap to an agent that already knew the best strategy. The question is how quickly regret can be forced down.
This work studies episodic tabular Markov decision processes: finite sets of situations and actions, reset after fixed-length rounds. The algorithm's exploration bonuses, extra rewards for visiting under-tested situations, adapt to visit counts and outcome variability. Earlier methods forced optimistic estimates; this one does not.
Its expected regret matches the theoretical lower bound, with no extra logarithmic factors. With many episodes, this removes a hidden gap between theory and practice.
