Publish date:

Superstar Effect

The numbers show that when Tiger Woods is in a funk, his competitors flourish

The on-course struggles of Tiger Woods have returned a healthy dose of that thing called competition—as in, anyone can win—to the PGA Tour. But the emergence of other pros is not due to Woods's kittenlike play alone. A recent study proves that when Tiger plays poorly his rivals play better, and, conversely, when he plays better they play worse, making fewer eagles and more bogeys.

Jennifer Brown, an assistant professor of management and strategy at the Kellogg School of Management at Northwestern, analyzed data from every PGA Tour event from 1999 to early 2010 and found that other players scored worse when Tiger participated in a tournament. The reason, Brown says, is that the players have a deep-down sense that they cannot win when Tiger is hot and are thus playing for less money and prestige, making them less likely to push themselves to their limits.

"In economics, it's a perfectly rational thing," Brown says. "Why should I exert costly effort in a contest that I will almost certainly lose? Not to say that competitors go out and don't try at all, but when making a rational decision, [it's as if] they're saying, The probability that I will win is lower, so I'm going to back off a little bit."

Over the decade of her study Brown found that players competing in an event with Woods took, on average, about a full stroke more than they did when Tiger was not in the field. Also, the players more directly in competition with Tiger—those high up the leader board—were more prone to the Superstar Effect, adding about two strokes. On average, less than two strokes separate first and second place on Tour, thus, Brown estimates, Woods pocketed an extra $5 million because of the reduced efforts of his opponents. "The guys who were close to the superstar in [scoring] were the ones who felt it most," Brown says. "If you're 65th, you're far enough away from the action that it doesn't really matter if Tiger's at the top or not."

Data from 2003--04 confirmed that the Superstar Effect hinges on the superness of the star: When Tiger slumped in 2003--04—as he is doing now—the rest of the field's scores improved. In other words the Superstar Effect disappeared. "To be recognized as a superstar," Brown says, "you have to play like a superstar and have other players react to you that way. In '03 Tiger was still a prominent figure on the Tour, but when he wasn't playing well, he didn't have that same empirical effect."

So for any Tour player who is suddenly experiencing an acute case of Tiger-directed schadenfreude, at least he can claim he's simply acting in the interest of his own game.


Golf Plus will next appear in the Sept. 20 SPORTS ILLUSTRATED.



Luke Donald 26%

Paul Casey 24%

Justin Rose 23%

Padraig Harrington 16%

Edoardo Molinari 11%

"Bernard Langer. Are you kidding me? He'll kick all their butts."

—Tom Patri, Friar's Head Golf Club



LONG SHADOW A study proves that when Woods is on, other players' scores go up.