As an invasion biologist, the process of spatial spread is at the heart of what I do. When I came across this dataset of Walmart store openings since 1962 I couldn’t help but see it as an invasion front which looks a lot like a biological invasion or (albeit slow) epidemic. The video shows monthly 






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