May 23, 2001
The Daily Prospectus
One of the things we're always yammering about is control of the strike zone. We evaluate players based on their on-base percentage and walk rate and pitchers by their strikeout-to-walk ratio. We emphasize--some would say overemphasize--plate discipline for hitters and control for pitchers when we talk about minor leaguers, and often tout players for no apparent reason other then they have this one very important skill.
If it's so important, it should show up on the scoreboard, right? Teams that draw walks and whose pitchers don't give them up should see that difference show up on the scoreboard.
The following chart shows each teams "Walk Gap", its rank in the league, and then its run differential and rank in that category.
Only five of the 14 teams in the AL have a positive walk gap, but four of those five have large positive run differentials. The five include the three best teams in the league and all of the five are at .500 or better. At the other end, three of the worst four walk-gap teams have three of the four worst run differentials.
The outlier is the Red Sox, who are third in the league in slugging and batting averages on the offensive end, and lead the AL in lowest batting and slugging averages against on the pitching side. You can make up for an unimpressive walk gap, but that's the kind of performance you need to pull it off.
The relationships are less clear in the National League. The two worst walk-gap teams are fourth and sixth in the league in runs, respectively. Two teams with positive walk gaps are among the four worst in the league in run differential. Two of the three highest-run-differential teams have slightly negative walk gaps.
My first reaction was that intentional walks might be screwing this up in the NL, but the effect is small. If you take out IBBs, the Marlins look even worse and are still last; the Brewers move up a few slots, but really, the list looks pretty much the same.
I'm going to head back to the lab and look at some data from other seasons to see if the walk gap has the significance I believe it does.
Joe Sheehan is an author of Baseball Prospectus. Contact him by clicking here.