You would say transposition vs substitution but there a few different string metrics. I picked one of the most popular which treats substitution as the same as

You would say transposition vs substitution but there a few different string metrics. I picked one of the most popular which treats substitution as the same as transposition. http://en.wikipedia.org/wiki/Levenshtein_distance http://en.wikipedia.org/wiki/Levenshtein_distance It shouldn't be hard to argue and force them to disclose what string metric they are using and what distance is the minimum if you're prepared to take them to court.