Once in a while, you embark on what looks like a simple computational procedure only to encounter frustration very early on. “I can’t even read my file into R!” you cry. Step back, take a deep breath and take note of what the software is trying to tell you. Most times, you’ve just missed something 

















Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).