Story Name: Home Runs
Datafile Name:homeruns.xls

Abstract: What is the relationship between the number of home runs that a major league baseball team hits and its team batting average? On one hand, we might expect better hitting teams to have both more home runs and higher batting averages. For individual players this is true: The correlation is about r = 0.2. On the other hand, teams have different styles of play and play their home games in different stadiums. Some may favor the home run, while other teams rely on singles and speed. The correlation between a team's home runs and its batting average is very close to zero, at r = -0.082. Examination of the scatterplot shows that this low correlation is due to three outlying teams with high batting averages and low home runs. Among the other teams there appears to be a weak positive relationship.

Image: Scatterplot of home runs vs. batting average