This is an important book. Roderick P. Hart and his coauthors have extended a long line of research that focuses on presidential style. Starting with Verbal Style and the Presidency (1984) and including his masterful The Sound of Leadership (1987) and Campaign Talk (2000), Hart has led the way in computer-assisted analysis of presidential discourse. In this latest book, the authors turn to the matter of tone.

Admitting that tone is a difficult concept to define and that its workings often seem mysterious, the authors nevertheless do an admirable job of clearly defining their topic and setting forth the assumptions underlying their analy­sis. “Tone,” they argue, “is a subset of style” (p. 8) and “a tool people use to create social impressions via word choice” (p. 9). Analysis of word choices is what this book is all about.

Using a data set of some 30,000 texts, all of them drawn from the ongoing Campaign Mapping Project at the University of Texas at Austin, Hart and his coauthors use the multiplatform program DICTION 6.0 to analyze talk—talk by presidents, talk by citizens, and talk by reporters. The DICTION program is sophisticate