In this part, we consider the application of FMCI to pattern statistics. After a short introduction of notations (section 4.1) we explain with an example in section 4.2 how to build through the tool of DFA a particular FMCI related to a given pattern. The block structure of this FMCI (section 4.3) is then used to get in section 4.4 two efficient algorithms for under- and over-represented patterns. We derive in section 4.5 some asymptotic developments but unlike with local score application, these results are not used to improve our algorithms. In the last section 4.6 we finally compare this new method to existing ones.