(This article was first published on SAS and R, and kindly contributed to R-bloggers)
The plot of Amazon sales rank over time generated in example 7.14 leaves questions. From a software perspective, we'd like to make the plot prettier, while we can embellish the plot to inform our interpretation about how the rank is calculated.For the latter purpose, we'll create an indicator of whether the rank was recorded in nighttime (eastern US time) or not. Then we'll color the nighttime To leave a comment for the author, please follow the link and comment on his blog: SAS and R.
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Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).