masz (the z is silent) is a tool that helps Checkusers see similarity of stylometric measures in discussions to find people with multiple accounts. The tool is behind OAuth and people who are not checkusers can't see similarity of two users as it can disclose legitimate sock puppets.

The code for it is licensed GPLv3 but it's not public. If you want access, let me know.

Here's an example:

not socks
Here's an example of two socks in Persian Wikipedia and two users that are not, analysed using a simple NLP system.

See also edit