B Acknowledgments

Software development is a collaborative enterprise. My everyday work as a social scientist depends mostly on tools that other people freely write, maintain, and distribute. I thank all of those who maintain R and the infrastructure that supports it. I am particularly grateful to those who helped me in the course of writing this book, whether directly by their help and comments, indirectly by independently solving problems I ran into myself, or unwittingly by the excellent example of their open and generous style of work: Jenny Bryan, Mine Çetinkaya-Rundel, Dirk Eddelbuettel, Thomas Lumley, Torkild Lyngstad, John MacFarlane, Bob Rudis, Hadley Wickham, Claus O. Wilke, and Yihui Xie.

Conversations with Jim Moody, Steve Vaisey, and Chris Bail got me started on this project. Duke University gave me time to see it through. I am grateful to students at Duke, Yale, McGill, the University of Oslo, and Statistical Horizons for being test-pilots for much of the material.