According to a new study co-authored by David Berri, an economist who runs the sports blog
Wages of Wins, most NBA coaches are similar to company managers. In the study, Berri and his colleagues sought to investigate whether Adam Smith's theory that workers make up the value of an organization—and that managers are nothing more than "
principal clerks"—applies to the NBA. The economists looked at a group of 19 longtime NBA coaches that had helmed multiple teams, using a Bill Jamesian statistic called Win Score to evaluate how players performed under their tutelage. Only eight of the 19 coaches had any statistically discernible effect on team performance. Seven had a positive impact, with Phil Jackson topping the chart. Next on the list: Rick Adelman, Rudy Tomjanovich, Rick Carlisle, Don Nelson, Flip Saunders, and Gregg Popovich. The only coach who had a demonstrably negative impact on his players: the
historically inept Tim Floyd. (For what it's worth, Berri didn't study Isiah Thomas. The NBA coaches study hasn't been published yet; a version of it will be included in the 2009 book
Stumbling on Wins, by Berri and Martin Schmidt.)More interesting than the names on Berri's list is his finding that the influence of even the best coaches was statistically very small and was distinguishable only from the worst-rated coaches, like Floyd. Even title-winning, Hall of Fame coaches like Pat Riley and Larry Brown were shown to have almost no impact on their teams. Players leaving Riley-led teams actually got better (except, it seems, for Antoine Walker).