Jane Street

Interview Question

Quantitative Trader Intern Interview
Jane Street

I sample p uniformly from [0,1] and flip a coin 100 times. The coin lands heads with probability p in each flip. Before each flip, you are allowed to guess which side it will land on. For each correct guess, you gain $1; for each incorrect guess, you lose $1. What would your strategy be, and would you pay $20 to play this game?

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