(This article was first published on is.R(), and kindly contributed to R-bloggers)
How to choose the right *apply function: This is an amazing stackoverflow answer to help you decide which of the many *apply functions (apply, lapply, sapply, vapply, mapply, rapply, tapply) is appropriate for the task at hand.
I’m planning on doing some future post on some subset of these functions (and I use them when needed in many of the Gists posted here), but I had to share this very comprehensive source.
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Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).