A modern account of categorical data analysis using the popular R software, this text covers model building and assessment methods for binary, multicategory, and count response variables and discusses fundamentals, such as odds ratio and probability estimation. The authors give detailed advice and guidelines on which procedures to use and why to use them. The text incorporates numerous examples from medicine, psychology, sports, ecology, and other areas, along with extensive R code and output. Data sets, R programs, and in-class recorded videos are available on the book's website.