Changing norms of comparison functions

Hi,

Maybe a dumb question, but how do you change the norm when you apply different comparison functions? In my case I'd like to change the LCS norm from "dice" to "overlap", but 

`compare.string('Name', 'Name', method='lcs',  label='Name_LCS', 'norm'='overlap')`

does not seem to change the norm, so I guess there's somewhere else to apply kwargs?

Thanks!