Ballpark Update

I received a number of e-mails today in response to the ballpark factor article. A couple of e-mailers said that ballpark factors can only be useful if they are tied to more specific types of batters or pitchers, such as lefty/right.

I absolutely agree that ballpark factors should be applied to different types of players, but I think that there are tremendous sample size and data interpretation issues. For instance, one e-mailer stated that Bonds does well in Pac Bell because it favors left-handed batters. But over the last three years, Bonds has slugged .829 at home and .789 on the road — hardly enough of a difference to support a separate “left-handed Pac Bell park factor.”

On the other hand, ballpark expert Kevin Johnson sent the following citation regarding offseason changes at Bithorn Stadium, which should have been included in my article (if only I had known!):

Hiram Bithorn Stadium has a new look and Bobby Cox approves. Last year’s hard artificial turf has been replaced by Field Turf, which better duplicates real grass, and the outfield fences have been moved back 10 feet to Montreal’s Olympic Stadium dimensions. The result has been a drastic reduction in home runs.

“I think it was much easier to hit one out last year and the new carpet has made it slower,” Cox said. “I think it’s good. Last year it played a little small.”

The increase to 404 feet to center and 375 feet to the power alleys isn’t the primary reason balls are no longer flying out of the stadium. The trade winds are blowing in, knocking balls down and preventing the Expos from even reaching the warning track with most of their drives.

Source: The Macon Telegraph. Thanks, Kevin!