Statistics.

You may also be interested in my UseR! 2010 short course.

R packages

• anchors: Tools for analyzing survey vignettes with Jonathan Wand and Gary King.
• eiPack: Ecological Inference and Higher-Dimension Data Management with Ryan Moore and Mike Kellermann implements extreme case analysis, ecological regression, RxC ecologial inference, and an array of methods to deal with higher-dimension data, such as simulations from EI tables.
• Zelig: Everyone's Statistical Software! Makes R easier to learn and use, with Kosuke Imai and Gary King

Statistical computing help

• Building R packages under Windows XP
• An R cheat sheet