[dahart]

Noise is a reality and a potential problem in ranking candidates for sure, 100%. Of course it’s worse than just measurement noise; the noise in hiring is subjective and situational and human. The sampling method doesn’t fix it, using the Secretary Problem approach doesn’t give you less noise, it gives you more noise in the result. The benefit of stopping early is that it reduces the cost of sampling, but if the company doesn’t care about the cost of sampling, there is no “problem” there to solve.

If you want to reduce noise, the way to do it is to have more independent measurements (interviewers), not to stop interviewing early.

The good news is that there’s no such actual thing as “best” in this situation and people have many dimensions, they can’t be ranked perfectly, but they can still be ranked approximately. We also don’t need to get the exact 30 people out of 100k people with infinite precision, we will get an amazing set if we can take a random sample of the top 1000 candidates out of 100k candidates. Having 100k candidates gives us the opportunity to end up with a selection from the top 1%, say, whereas if the number of applications was 40 people for 30 jobs, you might be stuck accepting people who are below average.