Recently there was a lot of racket about results presented in papers by a pair Nicholas Christakis & James Fowler. Their papers gained a lot of attention both in the academic world as well as in media. In their papers they claim to provide evidence for social contagion (transmission through social networks) of several types 
Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).
