Expected Winnings in a Random-Walk Money Collection Game on 45 Stones
Company: DRW
Role: Quantitative Researcher
Category: Statistics & Math
Difficulty: hard
Interview Round: Onsite
Overview: Random-walk puzzle in which a token moves one step either way around a circle of 45 stones holding 100 dollars each, while two players alternate coin-toss moves and collect money from stones they reach first. Asks for your expected winnings when the opponent moves first, testing linearity of expectation and first-passage arguments.
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