There is a common perception out there that Moneyball—the book about the Oakland Athletics written by Michael Lewis and soon to be released as a major motion picture—is mostly about a team racking up players with high on-base and slugging percentages.
In a sense this is true.
The story was mostly about the A's contending against richer teams by acquiring undervalued players and using statistics to determine which players possessed undervalued skills, and getting on base and slugging were indeed undervalued in the baseball player market.
It has become more difficult for the A's to contend because more teams and richer teams have since caught on. Almost every team now appropriately values things like on-base percentage, slugging and walks. There are no-doubt still market inefficiencies.
But Oakland being able to contend in the early 2000's wasn't just about taking advantage of market inefficiencies, though the team certainly did. If it were the case that it was all about taking advantage of market inefficiencies, I'm not so sure that they wouldn't have been able to find new inefficiencies that would have allowed them to keep contending.
What allowed the Athletics to contend was that the player market did not appropriately value the most valuable aspects of a player's game.
On-base percentage correlates to winning better than any other rate statistic. Slugging also has a high correlation to winning.
Teams that get on base and slug best are the teams that score the most runs. Teams that keep their opponents off base and prevent them from slugging well are the teams that prevent runs. Go ahead and try to find a counter-example to this concept throughout baseball history.
You simply can't.
Many teams weren't just misguided, ignoring certain positive skills in the marketplace. They were really misguided, ignoring the most fundamentally important aspects of what makes good teams good.
It's pretty amazing when you think about it.
Major League teams largely didn't view the game through the lens of outs and out-avoidance or gaining bases through slugging.
Sure, the mid-1990's Yankees focused on on-base percentage throughout their system. Sure, teams long before that were aware that getting on base was a vital part of the game. But it wasn't brought to light in a major way until Michael Lewis and Moneyball.
The caricature of Billy Beane is that of a guy who thinks he's a statistical genius and the reality is that the A's truly owe their success to three great pitchers: Tim Hudson, Mark Mulder and Barry Zito.
But the genius of Beane, to the degree that he is a genius, wasn't that he reinvented the wheel with statistics. It's that he did what few other teams in baseball history had done, and just paid attention to the fundamentals of the game. Those fundamental aspects also happened to be undervalued in the baseball player market.
Moneyball could have been written about a variety of teams, but the Oakland A's were a perfect storm. They weren't just taking advantage of the fact that on-base and slugging percentages were undervalued; other teams throughout baseball history have taken advantage of that, as well.
They were also a relatively poor team coming along when the narrative in baseball was all about how poorer teams could never hang with the richer teams because the richer teams would be able to buy the best players.
The A's and Billy Beane didn't really do anything that other teams in baseball history hadn't already done. They just realized that most other contemporary teams with whom they were competing weren't doing those things at that particular time, and that if the A's did those things, they could contend.
Michael Lewis discovered this and wrote an excellent book about it, a book and soon-to-be movie that changed baseball.