Software is a kind of condensed collaboration. It’s a big help in everyday life but it is also easy to take for granted. The research and teaching I do depends on tools that other people freely write, maintain, and distribute. My first debt is therefore to all of those who produce and maintain R, the infrastructure that supports it, and the packages built on its foundations. The particular libraries used in the book are cited throughout the text and referenced in the bibliography. I am also grateful to those in the R community who helped me while I wrote this book, whether directly, though comments and suggestions; indirectly, by independently solving problems I ran into myself; or unwittingly, via the excellent example of their own open and generous style of work. In particular I thank Jenny Bryan, Mine Çetinkaya-Rundel, Dirk Eddelbuettel, Thomas Lumley, John MacFarlane, Bob Rudis, Hadley Wickham, Claus O. Wilke, and Yihui Xie.

A conversation with Chris Bail, a co-authored paper with Jim Moody (Healy & Moody, 2014), and a suggestion from Steve Vaisey got me started on this project. Duke University and the Kenan Institute for Ethics gave me time to see it through. Martin Ruef and Suzanne Shanahan made the necessary room. My students and seminar participants at Duke, Yale, McGill, the University of Oslo, and Statistical Horizons were test-pilots for much of the material and provided invaluable feedback. I thank Andy Papachristos, Tom Lyttleton, Torkild Lyngstad, Amélie Quesnel-Vallée, Shelley Clark, and Paul Allison for the external teaching opportunities.

At Princeton University Press, Meagan Levinson has been an ideal editor in every respect. Her expert guidance and enthusiasm throughout the writing and production of the book made everything move a lot quicker than expected. Four anonymous readers for the Press provided detailed and helpful comments that improved the manuscript substantially. I also received excellent feedback from Andrew Gelman, Eszter Hargittai, Matissa Hollister, Eric Lawrence, and Matt Salganik. Any remaining errors are of course my own.

For many years, Laurie Paul gave her encouragement and support to this and other projects. I thank her for that. Is cuma leis an mhaidin cad air a ngealann sí.

For their professionalism as colleagues or their kindness as friends I am grateful to Courtney Bender, Mary Dixon-Woods, John Evans, Tina Fetner, Pierre-Olivier Gourinchas, Erin Kelly, Brian Steensland, Craig Upright, Rebekah Estrada Vaisey, and Steve Vaisey. Marion Fourcade has both these qualities but also a third—patience as a co-author—that I fear I have tried beyond reason.

Much of this book was written on the Robertson Scholars Bus, which goes back and forth between Duke and Chapel Hill on the half hour during term. It’s a big help in everyday life but it is also easy to take for granted. Its existence is worth any amount of handwaving about connection and collaboration, however. The best seats are near the front, facing sideways. The WiFi is free but I recommend you keep it turned off if you want to get anything done.