Penalty kicks with a shifting rate
You take penalty kicks. You make the first and miss the second. From then on, the probability you score any kick equals the fraction of kicks you've made so far (e.g. after makes in attempts, the next has probability ). The probability that you finish with exactly made can be written as for an integer ; find .
Show hints (2)+
- It's a Pólya urn started with one make and one miss (score = past make-fraction, then reinforce).
- With a start the success count is uniform: total makes is uniform on .
Answer
Reveal answer →Final answer
99
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Asked at: Jane Street, Two Sigma