Interesting stuff.

I am not too familiar with this area, but there are other methods, see e.g. Handcock & Morris, Relative Distribution Methods in the Social Sciences http://www.amazon.com/Relative-Distribution-Sciences-Statistics-Behavioral/dp/0387987789/ref=sr_1_1?ie=UTF8&qid=1365001258&sr=8-1&keywords=relative+distribution+methods , although it's old.