A decade after moneyball, have the A’s found a new market inefficiency?
Posted by Dean Holden at February 17th, 2014
Originally published on Baseball Prospectus.
The Oakland Athletics finished 2013 with baseball’s fourth-lowest payroll, fourth-best offense, and best clubhouse chemistry. Debate has centered on whether the latter two are related. There’s nothing objectionable about “good guy” genes—it’s a solid organizational goal to have. But chemistry alone doesn’t put runs on the board, and if a team is missing the talent, they better find the runs elsewhere. The 2002 Athletics discovered them in walk deities and college arms; once those methods pervaded front offices, the A’s slipped back into losing. Was chemistry the only undervalued commodity of their recent resurgence?
As the baseball community obtains more knowledge, roster construction strategies evolve. Previously undervalued talents like walks and defense are now accepted constructs. The A’s are Hollywood-infamous for adopting them before their competitors while prices were low. After a 74-win 2011, they cheaply signed Brandon Inge and Jonny Gomes, who Brandon McCarthy claimed bolstered the clubhouse DNA to the tune of 20 wins. But Inge and Gomes were two of several players who also bolstered a less-visible statistic: fly ball-to-ground ball ratio.
Since 2009, fly ball rates (which exclude popups here) have gradually decreased. Oakland has defied this trend, ranking first from 2012-13. What caused the A’s jump? Let’s inspect their transaction logs, beginning with their acquisitions for 2012:
Is it a coincidence these seven batters had above-average fly ball rates when Billy Beane and his front office acquired them? Maybe. It’s less believable when reviewing his 2013 shopping cart:
This time, Beane spent more to fill premium defensive positions1. Their commonality is unmistakable: while fly balls around the league grew rarer, Beane stocked his lineup with air-inclined hitters. As a result, 60 percent of Oakland’s plate appearances last season were taken by “fly-ball hitters” (defined as a hitter whose ground ball rate is one standard deviation below the league mean)2. See how that compares to the rest of the league:
Let’s contextualize Oakland’s outlier ways: 60 percent of their plate appearances were taken by fly-ball hitters, who by definition compose 16 percent of the league. No other team in the past nine years has touched 45 percent. Beane’s roster was so ground-allergic that only 0.8 percent of their plate appearances were taken by “ground-ball hitters.” That’s not just a concentrated effort to target fly balls. That’s a mission statement.
The other platoon advantage
The Book: Playing the Percentages in Baseball devotes a chapter to platoon effects. Five pages discuss handedness, a mainstay of baseball analysis today. Two pages cover a less visible effect: batted-ball tendencies. Authors Tango, Litchman, and Dolphin found that fly-ball hitters had an advantage over ground-ball hitters, simply because they are better hitters—you can’t homer on grounders, after all. They also found that fly-ball hitters are especially good against ground-ball pitchers, because the former tend to swing under the ball while the latter want the hitter to swing over the ball.
However, Tango et al. noted that this platoon advantage is hard to exploit because players tend to be neutral rather than lean to either extreme. Also, the advantage itself is very small, and hence overshadowed by the handedness platoon. Such a minimal advantage would (theoretically) require being multiplied through several hitters to become meaningful.
So what happens when a determined, resourceful general manager decides to overhaul his lineup with fly-ball hitters, capitalizing on a league-wide trend toward ground-ball pitchers?
First, updating The Book’s findings using the above hitter definition (and applying the same for pitchers), here’s how each type of batter performs against each type of pitcher in True Average, from 2007-13:
Fly ball batters are nine points of TAv better than neutral batters. That’s the difference between Cleveland’s sixth-ranked offense and the Dodgers’ 10th-ranked offense. That’s a significant advantage! Here’s how often each matchup occurs:
This table doesn’t differ much from The Book’s version. Approximately two-thirds of batters and pitchers have neutral batted ball tendencies, and thus the majority of batter-pitcher matchups will not have this platoon effect in play. That is, unless you hit for the 2013 Athletics:
The 60 percent found earlier, segmented into pitchers faced. From above, fly-ball hitters have a .275 TAv—15 points above league average, and the mark of a top-five offense. If a team their distributed plate appearances this way, they would position themselves for offensive prosperity. How much did it help Oakland?
Moreover, Oakland fly ball hitters hit .302 against GB pitchers, a matchup occurring nine percent of the time. Another way of putting that: In 547 plate appearances against ground-ballers, fly ball-hitting Athletics (such as low-salary acquisitions like Jed Lowrie and Brandon Moss) hit like $16-million Matt Holliday. The rest of the time—over 90 percent of PAs—they hit like Chase Headley.The 38 percent of their fly ball hitters’ plate appearances against neutral pitchers resulted in a .282 True Average. That’s better than the solid league TAv in that matchup (.276)—and it occurred for the Athletics four times as often!
The Book claimed that managers weren’t using this platoon advantage enough. It appears that Billy Beane has, effectively transforming his batting roster into 12 Chase Headleys and a Matt Holliday.
But doesn’t O.co Coliseum stifle fly balls?
Yes, it still does. In fact, the Athletics hit .299 on fly balls—the 10th-worst TAv—and that’s park-adjusted. Their slash line on fly balls was a pitiful .197/.191/.615. The Boston Red Sox, who had the next-highest percentage of plate appearances taken by air hitters at 39 percent, had a .409 TAv on fly balls (.313/.302/.855)3