Deadspin has an
—the book that aspires to be the
of sports—in which the authors report on a startling statistical finding that a pair of Wharton economists made about baseball. Players who are hitting .299, they say, become totally different batters in their final at-bat of the season. When they need one last hit to reach the lovely, round .300 mark, batters stop taking walks. They become markedly more aggressive, and markedly more effective:
[W]hen these .299 hitters swung away, they’ve been remarkably successful. According to Pope and Simohnson, in that final at-bat of the season, .299 hitters have hit almost .430. In comparison, in their final at-bat, players hitting .300 have hit only .230.
The New York Times reported on the
this past October:
They found that the 127 hitters at .299 or .300 batted a whopping .463 in that final at-bat, demonstrating a motivation to succeed well beyond normal (and in what was usually an otherwise meaningless game).
…[H]itters will clearly try much harder when a .300 average is at stake, said Devin Pope, who co-wrote the study.
Ah, economic reasoning: arrogance standing on the shoulders of ignorance. Apparently it did not occur to the Wharton professors to ask whether anyone else had ever analyzed baseball statistics—say, to figure out how much of an influence “motivation to succeed” is known to have on a player’s performance.
For decades, people who study baseball have been trying to smoke out evidence that players can raise their games when they “try much harder.” It is the question that more or less defines the conflict between rational baseball analysts and the old romantic storytellers—can players ”
” or ”
,” or do they just get the results you’d expect from their overall averages? If trying harder really does work, nobody has discovered how to
Yet here were two members of a self-styled rational profession, hailing the visible effects of that invisible gremlin, motivation—whopping, obvious effects, across the board: 160 points of batting average! Why couldn’t the hitters just bear down all season long, and hit .460?
Because the finding was bunk. The baseball-statistics community pounced on the study and tore into its underbelly: motivation may not determine whether a player gets a hit, but it can determine whether a player plays. The economists hadn’t effectively accounted for the fact that when a .299 hitter got a hit and reached the .300 mark, he was likely to
. Players who didn’t get the hit would keep trying.
1. The factoid, “players hitting .299 or .300 batting a whopping .463 in their final at-bat” is true – but it’s the result of cherry-picking the AB in the sample. If the player got a hit to pass .300, it was likely to *become* his last at-bat, as he tended to sit out the rest of the season. But if he made an out, the AB wouldn’t be his last.
2. If you look at at *all* AB, not just the cherry-picked “last” ones, players around .300 hit only slightly better than expected, not statistically significant at all.
The Scorecasting authors acknowledge this, sort of:
Another way to achieve a season-ending average of .300 is to hit the goal and then preserve it. Sure enough, players hitting .300 on the season’s last day are much more likely to take the day off than are players hitting .299. Even when .300 hitters do play, in their final at-bat they are substituted for by a pinch hitter more than 34 percent of the time. In other words, more than a third of the time, a player hitting .300—an earmark of greatness—will relinquish his last at-bat to a pinch hitter. (Hey, at least his average can’t diminish.) By contrast, a .299 hitter almost never gets replaced on his last at-bat.
But they don’t seem to notice that it undermines their whole previous point. The lure of the .300 average does distort decisions about whether players play—and, as the authors go on to say, decisions about how much players get paid. (Though Vladimir Guerrero’s
last year didn’t seem to keep him out of the current
. Maybe if he’d hit 30 homers instead of 29?) That doesn’t mean it affects what players do when they do play.