MLB Gameday stores its game data in XML format, with the players denoted in ID numbers. To find out who is who, the codes are stored in pitchers.xml or batters.xml of each game. My DownloadPitchFX.R script can download the ID numbers, but it doesn’t look to see who the ID is because of the extra 


















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