An Exploration of Robot Javellin Throwing
My attempt at Jane Street's December 2025 Puzzle
Initially a problem I picked up for the fun of it, robot baseball very quickly grabbed my attention for its intensely convoluted presentation that boils down to one informational assymetry in a very symmetric game.
The Setup
Imagine two robots going head to head at the robot olympics. Both are separated by a wall, that for this case, stops any information going from A to B and viceversa. The javellin throwing is structured as follows, with each contestant trying to end up with the longest throw at the end.
assuming the distance of a single throw of either robot is distributed uniformly ($D ~ U(0,1)$), (…)