> About 15 went on to complete a reasonably simple real-world challenge I am not sure what you mean by better way of filtering. You already got only 15 candida

> About 15 went on to complete a reasonably simple real-world challenge I am not sure what you mean by better way of filtering. You already got only 15 candidates from 2500 applicants. Next step is to just check what they have done in the challenge which will further reduce the number of candidates. The problem would be if lets say 1000 applicants submit the challenge.