Are Pitchers From The South More Aggressive Than Pitchers From The North?

Social psychologists who want to learn more about aggression may want to head to their local baseball diamonds this summer.

According to a study in the May Journal of Applied Psychology (Vol. 92, No. 3), Major League Baseball (MLB) pitchers hit batters more often in situations that allow them to restore justice—in retaliation for a teammate being hit, for example. That may not be surprising to baseball fans, but a deeper analysis of these hit-by-pitch events, alongside personal characteristics of the pitcher and batter, such as race and birthplace, reveal trends that may make these events even easier to predict, says the study's author, Thomas A. Timmerman, PhD, associate professor of business management at Tennessee Technological University.

A better understanding of pitchers' motivations may help the league reduce hit-by-pitch events, which numbered more than 1,800 in 2006, he says.

Timmerman looked at MLB data on the 27,667 hit-by-pitch events that took place from 1960 to 2004. He found that pitchers were most likely to hit batters when the batter had hit a home run during their last at-bat, when the previous batter had hit a home run and when a pitch in the previous half-inning hit the pitcher's teammate.

Yet, at the regional level,Timmerman also found that, in all three of these situations, white pitchers born in states typically defined as Southern by the U.S. Census were 40 percent more likely to hit a batter than non-Southerners. This trend may be due to a Southern inclination to act aggressively when their honor is challenged, he says. Timmerman recommends that the league penalize any pitcher who hits a batter—intentionally or not.

Most importantly, says Timmerman, the study may help psychologists understand the intricacies of aggression theories.

"You have to look at the situation, the aggressor and the target, all at the same time, or else you'll find nothing," he says. "It really shows the complexity of studying aggression."