Don't Swing! You Will Walk to the First Base: Spot Fixing in the Korean Professional Baseball League

Abstract

The study is about spot fixing in baseball game where a pitcher issues the first base on balls of the game (first-BB fixings, hereinafter) directed by gambling brokers in an attempt to make profit by betting accordingly on illegal gambling sites. After the Korean prosecutors charged two starting pitchers for their involvement in spot-fixing during the 2011 season in the Korean professional baseball league, baseball fans began to wonder whether there were more players involved and whether such criminal activities were widespread in the league. This empirical study attempts to answer those questions. In specific, the study addresses three issues:Issue 1 – Statistical evidences of the two corrupt pitchers (DD and DDD regressions)Issue 2 – How about other pitchers? Check the BB tendency in the second inning of the suspected pitchers.Issue 3 - Comparison between Korean Pitchers (treatment group) and Foreign Ones (control group)Our findings are as follows:1. Statistical evidence confirms that the two pitchers charged committed the first-BB fixings in the 2011 season, which is consistent with the prosecutor’s investigation report. On the contrary, the 2009 and 2010 seasons statistics of the two pitchers don’t present the same evidence.2. Statistical investigation, including DD regression by each pitcher, found no other doubtful pitchers. In addition, DD regressions on all Korean pitchers and even on the group of suspected pitchers couldn’t reject the null hypothesis that they didn’t commit the first-BB fixing.These results imply that the first-BB fixing was not widespread in the Korean baseball league. This result, however, does not guarantee that other types of spot fixing were not prevalent in the Korean baseball league during that period.