Pitch One to Ball Four: Part One

One of my more peculiar fascinations is with the first pitch of at bats. Specifically, I seem to pay an inordinate amount of attention to players and teams that swing at the first pitch more or less often than you would expect. With the pitch-by-pitch database that I happen to have, it is actually a trivial exercise to extract that information, so for tonight I decided to take a look at the first pitch on a team level for 2008.

Namely, I wanted to investigate the percentage of first pitches that a given team swung at. For additional context, I included that team’s walk rate under the theory that you would expect some negative correlation between how often a team swung at the first pitch and how often they drew a walk. The difference between the two is included as the final column with a positive difference expressing that the team drew more walks than expected.

Despite the promising sign of the top and bottom teams matching up perfectly, the dataset (limited as it is to just 30 data points) shows little correlation.

However, visual inspection reveals a possible pattern. It looks like a majority of the teams do follow a roughly a linear pattern between not offering at the first pitch and drawing walks, there might be two clumps perpendicular to the hypothetical trend line. There are two teams (Seattle and Pittsburgh) that took first pitches often but didn’t translate those into walks and a clump of six teams (Atlanta, Texas, Tampa, Chicago(N), St.Louis and Cincinnati) that drew walks at an above average pace despite offering at the first pitch more often than average.

Is there something (like a higher or lower percentage of free-swinging, high-slugging hitters) about the make up of the teams in those two groups that helped distinguish them from the other 22 teams, who show a correlation of 0.78 between the two axes? In part two, we’ll add in some data from past years to get a bigger sample size and if the pattern holds, see if we cannot tease out a possible explanation.