(This article was first published on SAS and R, and kindly contributed to R-bloggers)
Pyramid plots are a common way to display the distribution of age groups in a human population. The percentages of people within a given age category are arranged in a barplot, often back to back. Such displays can be used distinguish males vs. females, differences between two different countries or the distribution of age at different timepoints. Aidan Kane has an example.We demonstrate how 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).