5 min readReinforcement Learning
The Parameter Nobody Chooses
The living reward in a grid world is written down once and never discussed, and the optimal policy is a step function of it: eight thresholds between -3 and 0, each flipping exactly one square. The textbook value of -0.04 sits 0.0048 away from the one that decides whether the agent takes the shortcut past the pit, and above -0.0221, when steps are nearly free, the optimal move in one corner is to walk into a wall on purpose.
Artificial Intelligence