nltk/nltk — pull request #618 by jnothman (2014-02-20 23:45:16+00:00)
Title: Add approximate tests for association measures

This adds tests for association measures. I've used numbers from Manning and Schutze where possible, and it seems we had a 2x multiplier in `likelihoo_ratio` that they don't use. Where known numbers aren't available in _SNLP_, I've tested the relative ordering under different measures.