MediumProbability
The Secretary Problem
Jane StreetDE Shaw
You interview 100 candidates in random order, must accept or reject each on the spot, and want the single best. The optimal rule observes and rejects an initial fraction, then takes the first candidate better than everyone seen so far. Roughly what percentage should you observe first?
Approach
Balance learning the field against the risk the best is in your rejected sample.
The magic number is 1/e.
Answer
Show the final answer
The answer is 37. Sign in free for the full worked solution and to check your own answer.
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