As I explained on Monday, I was blessed with an opportunity to review Toby Moskowitz and Jon Wertheim’s book Scorecasting but was incapable of leaving the review to one post. On Monday, I took a quick look at the Rays’ 2010 attendance numbers that seemed to confirm that the Rays, like most other Major League teams, have an economic incentive to win games.
Toby and Jon had another incredible insight into the world of sports that raised an interesting question about Tropicana Field and is the subject of part 2 of my review. In their research, Toby and Jon ably prove that there is, in fact, a home field advantage in almost every sport. They conclude that the home field advantage exists because game officials in every sport side with the home team on judgment calls in crunch time.
Basically, Jon and Toby prove that game officials are subject to the same psychological phenomena as normal people and, when put in an environment surrounded by a group of people are hoping for the same outcome, those officials tend to exercise their judgment in favor of the crowd’s desire. In baseball, that means home teams give up fewer unintentional walks, strike out more hitters, turn more double plays, and catch more runners stealing.
Upon reading that conclusion, anyone that follows the home nine assuredly is asking the same question that popped into my head: “What if the visiting team brings a ‘home’ crowd?” More directly, can all those bandwagon Yankee fans and pink-hatted Red Sox fans actually “steal” the Rays home field advantage at the Trop?
Maybe but, it doesn’t look like they have.
I looked at the Rays splits versus Boston and New York in 2010. In both scenarios, the Rays fared better at home than they did on the road in all of Jon and Toby’s discretionary categories. For example, in 2010, Rays pitchers unintentionally walked .8 more hitters per nine innings in Yankee Stadium than they did against the Yankees at the Trop. But, Rays pitchers only fanned .12 more Yankee hitters per nine innings at the Trop than they did at Yankee Stadium. Similarly, the Rays’ staff walked 1.4 more hitters per nine innings at Fenway Park than they did against Boston at the Trop and fanned 1.6 more Red Sox per 9 at home than they did on the road.
In fact, the Rays’ home/road splits against Boston and New York in Jon and Toby’s discretionary categories, are nearly identical to their splits against every other team.
Does that mean the Red Sox and Yankees never flipped the Rays’ home field advantage? No.
Admittedly, 2010 is a small sample size (just 36 games). But, most of the data from the Rays’ history isn’t useful so we are left with 2009 and 2010.
Evaluating whether New York or Boston were the “home” team in Tampa Bay between 1998 and 2007 is difficult, in part, because the Rays teams during that period were so bad. The Rays poor performance reduced the number of high-leverage situations when Boston and New York were in town and, according to Jon and Toby, high leverage situations expose the most home field bias.
Moreover, until the end of the 2008 season, Tropicana Field was one of 6 parks in the Majors to using MLB’s Questec umpire evaluation tool. According to Jon and Toby, when evaluating the 6 parks using Questec, they saw a reversal of the home field umpiring trend. They conclude, reasonably, that the known presence of Questec motivated umpires to actively assist the visiting team in an effort to avoid the appearance of home team bias. So, to the extent that the Yankees or Sox performed better than expected at the Trop before 2009, it is at least as likely the result of Questec than it is the result of the crowd.
That leaves the Rays injury-plagued 2009 and their AL East title run in 2010. Both polar extremes in some respects. I am encouraged to see that the Rays held a home field advantage over their AL East rivals that roughly mirrors what you’d expect for the “home” team in 2010. But, I don’t want to read too much into such a limited number of games. At the very least, we can agree that there is no evidence that the Yankees or Sox have “taken over” Tampa Bay.







