Moneyball and the Baseball Players’ Labor Market

Abstract

Michael Lewis's best-selling book, Moneyball, demonstrated the efforts of Oakland A's General Manager, Billy Beane, to create a successful baseball team in spite of its location in a small market. Previous studies have argued that the salary returns to the neglected skill of on base percentage (OBP) should rise once the Oakland A's hitters demonstrated proficiency with this skill. Our key result is that after Moneyball was published in 2003, hitter salaries for free agents signing new contracts were not more closely related to OBP. Consistent with efficiency, we find no long-term change in valuation in OBP. In contrast, we do find evidence of a rise in salary returns to productivity in the form of bases per hit (‘power hitting’) but this again is consistent with efficient market adjustment. In sum, it appears the labor market for hitters in baseball was efficient both before and after the appearance of Moneyball.