Function tolerance_rank 

pub fn tolerance_rank(count: usize) -> usize

The rank, counted from 1 in ascending order, of the leave-one-out median that is the tolerance of count renders: ⌈0.95 (count + 1)⌉, at most count.

A clip of the same sound and the renders are exchangeable, so the clip’s median lies at or below the median at this rank with a probability of the rank over count + 1: 20/21 for 20 renders. With fewer than 19 renders the rank stops at count, and the coverage falls below 95 %.