Baseball Myths

SCIENCE JOURNAL
By SHARON BEGLEY

A New Study Shows
How Baseball Myths
Can Hurt the Game
February 16, 2007; Page B1

After St. Louis won the 2006 World Series, you'd think fans in small cities would stop grousing that major-market teams have a built-in edge. Should any of you not be inclined to concede error, economist J.C. Bradbury is ready to regale you with statistics, regression analysis and Cartesian plots to prove mathematically that, while big-market baseball teams win more than small-market teams do, market size explains only part of the differential.

With pitchers and catchers reporting to the grapefruit and cactus leagues this week, it's time for baseball fans to dust off the equipment they, too, need for the 2007 season. I am referring, of course, to calculators, statistics, economics and multiple regression analysis, which calculates how much one factor (such as market size) contributes to some outcome (team wins).

In the hands of Prof. Bradbury, of Kennesaw State University, Georgia, these techniques lead to counterintuitive results sure to spark a bar fight or two. His coming book "The Baseball Economist: The Real Game Exposed," takes aim at all sorts of baseball lore to separate fact from myth.

Ever since the American League introduced the designated-hitter rule in 1973, its rate of batters-hit-by-a-pitch has exceeded that in the National League by a total of 15% through 2005. Economics offers a simple explanation. In both leagues the cost of hitting a batter with a pitch is having a man on base. But in the National League, where pitchers bat, there is also the cost of risking a retaliatory beaning when you, the wild hurler, step up to the plate. Ergo, more hit batsmen in the AL.

But retaliation explains only part of the NL/AL difference. The NL hit-batter rate equaled, and sometimes exceeded, the AL's after expansion years (1993 and 1998). The presence of more wild pitchers in the NL (which had more new teams) swamped the deterrent effect of possible retaliation, which turns out to be only a minor factor in the hit-batsman rate.

Baseball wisdom holds that a team needs to "protect" its star slugger by having a decent hitter behind him. By this reasoning, the Mets' Carlos Beltran last year belted so many home runs (41, a career high, after 16 in 2005) because Carlos Delgado hit behind him, and Barry Bonds would have gotten fewer walks if Albert Pujols instead of Jeff Kent had been on deck. A good on-deck hitter supposedly keeps a pitcher from pitching around a strong batter; a weak one makes a pitcher more willing to walk the slugger.

Prof. Bradbury shows otherwise. If the on-deck hitter is a threat (think Boston clean-up hitter Manny Ramirez), then putting the slugger (David Ortiz) on base carries a steeper price: Manny has a good chance of driving in Ortiz. The three-spot hitter may therefore get fewer walks if there's a strong clean-up batter, and the strikes he sees may be even harder to hit because the pitcher reaches back for extra speed or movement to keep him from reaching base and therefore setting up an RBI. A pitcher might let Ortiz reach base if a .150 hitter waited on deck, but ratchet up his effort if he sees Manny there.

Speculation is fine, but Prof. Bradbury prefers multiple regression analysis. Using this technique, he and a colleague found that a weak on-deck hitter makes a batter more likely to get an extra-base hit. A strong on-deck hitter lowers the chance that the batter before him will walk, and also lowers his chance of hitting for average and power. "Protection," Prof. Bradbury concludes, "is a myth."

So is the popular explanation for why there are no left-handed catchers, namely, that a lefty would have a tougher time throwing out runners at third than a righty does. Prof. Bradbury analyzed data from tens of thousands of game situations to count how often various on-base/out configurations led to a run. The difference in runs scored with a man on second rather than third -- a measure of how important it is to throw out a runner trying to steal third -- is a puny 0.4 per game.

Even that overstates the case, because runners on second don't steal every time third is open. That happens only 13.7% of the time. Protecting against the steal is therefore not a convincing reason to have only right-handed catchers; stealing third is rare, and even when it succeeds the gain is small. Lefties don't catch because managers have four other positions to play them (three outfield slots plus first base), and so don't need to put them behind the plate.

Assembling a fantasy team? Prof. Bradbury finds that the best predictor of a hitter's production is not average, RBIs or runs scored. It is on-base percentage plus slugging average. This sum accounts for almost all the difference in how many runs a player will be responsible for.

Oh, and the big-market/small-market question. Every 1.58 million residents produces one extra win per season, Prof. Bradbury calculates, using data from 1995 to 2004. Based on population alone, the Yankees should win 10.61 more games than Milwaukee.

Calculating "population-adjusted wins," he shows which teams did better than their city's size predicts -- and which did worse. I'm talking about you, Kansas City, Pittsburgh, Tampa Bay and Milwaukee.