Moneyball

The word “sabermetrics” refers to the application of statistical analysis to predict and compare the performance of individual baseball players. It is the acronym of the Society for American Baseball Research. Even though I am a lifetime baseball fan and a Founding Father of the exclusive Red Sox Nation, I had never heard of the term before I saw “Moneyball,” the film based on Michael Lewis’ Moneyball: The Art of Winning an Unfair Game.

Lewis claims that baseball is unfair in the sense that money rules, that teams with the most economic clout attract the “best” players since they can offer them outrageous salaries. In contrast, the teams that are least successful have with far less financial resources to pay their players. For better or worse, talent seems to flow in the direction of cash.

But what is talent? That is the question sabermetrics addresses. According to Lewis and those voiced by the characters in the film, predictions of player success made by baseball scouts and other insiders are flawed because they are based on subjective views of factors that have little relationship to empirical measures of player performance.

The film recounts the tale of the Oakland Athletics beginning in 2001 when they almost beat the Yankee’s in the American League playoff series. In the following year, the Athletics spent $42 million on player salaries while the Yankees had a $125 million payroll. The Athletics began that season without the three best players on their 2001 team by loosing their first 11games.

At this point the Athletics general manager, Billy Beane, played by Brad Pitt, realizes he and his scouts are not asking the right questions. In a timely meeting with a recent Yale graduate in economics, Peter Brand, played by the perfectly cast nerdy-looking Jonah Hill, he is introduced to the sabermetric approach to building a successful baseball team.

Brand persuades him that slugging and on-base percentage measures are far more effective than conventional offensive measures of batting average, runs batted in and stolen bases. Sabermetrics also analyzes performance measures with a rigorous set of equations unlike the more intuitive, “clinical” methods usually employed by baseball insiders and scouts. In addition, players scoring well on the basis of a sabermetrics assessment are much cheaper to sign than those selected by traditional methods.

Once Beane began hiring players on the basis of this statistical analysis, the Athletics began to win games. Although they didn’t win the World Series in 2002, loosing in the playoff series after finishing first place in the American League Western Division, they did win 20 straight games, a League record of successive wins that stands to this day.

Aside from the intelligence and power of the film, the issue it tackles has widespread implications. What is the most effective method of predicting behavior? The standard view holds that personal experience, clinical judgment, sometimes called instinct or intuition combined in some unorganized fashion and subject to all the biases and errors that combinatory methods often make, is the most effective.

In contrast, the statistical approach, empirical or evidence-based approach, combined on a fixed quantitative basis, is the most effective. Assumptions are built into the statistical models, yes, but they are adhered to consistently and can be changed in the light of further evidence.

The relative merits of these differing approaches have been compared in many fields—medicine, psychotherapy, correctional practices, and baseball to name but a few. The debate has gone on for years in spite of the fact that research has reliably shown that statistical decision making out performs clinical judgment. It isn’t perfect, but it clearly reduces the risk of error. Yet, because it challenges many long-standing practices, it is often strongly resisted.

“Moneyball” shows us how useful statistical methods applied to the prediction of baseball player success allowed the Oakland Athletics to achieve winning seasons despite the burden of severely limited player budgets. In fact, for years, the Athletics ranked first among all major league teams is dollars spent per games won. Can’t beat the facts, can you?