I know this will seem entirely counterintuitive, but perhaps the problem is that Tiger's opponents are trying too hard, not that they aren't trying as much as they would otherwise.

Golf is one of those sports where maximum physical effort does not necessarily translate to better results - if you hit driver at a short par 3 hole, you're a lot worse off than if you hit a 7 iron. Good course management, like laying up instead of going for the green in 2 on a par 5, can improve a player's score significantly over time.

But when you're faced with Tiger Woods, it could seem like the only way to beat him is to take chances, like going for that green or hitting a less-accurate driver off the tee instead of a 3 wood. The thing is that the reason you usually don't do those things is that they usually don't work as well as the safer choices. Of course, if everyone on the course who has a real shot at Tiger is doing those things, that would push their scores up on average, since the risks mostly won't pan out.

This hypothesis also accounts for the non-exempt players, for exactly the same reason as suggested in the article. They have no incentive to play any differently than usual because they don't really have a chance to win the tournament anyway. (And, besides, the lower-ranked golfers are less likely to want to risk missing the cut by taking chances, since the money from a single tournament matters more to them than to the exempt golfers.)

Finally, this explanation also has instintive appeal to anyone who ever watched Phil Mickelson slash his way around a golf course trying to catch up to Tiger, and then saw him succeed only when he decided to rein his game in for once.

I was going to say exactly the same thing.

The lowered scores are the result of a rational strategy in the face of superior competition.

The optimal winning strategy in golf is not necessarily the strategy that will get the best score, on average. A good player might be fully capable of shooting, say, 8 under par, and without Woods in the field, that's what they would do. But if they are faced with needing a 10 under par to win, they have to start taking chances, and (on average) they end up with a worse score then they would have otherwise (7 under par, according to this study).

The players are not idiots. They know this full well. But they are willing to do a little bit worse (on average) in order to have a chance of beating Tiger that one time.

An even starker example of this happens in figure skating competitions when one competitor is capable of landing a high risk jump, like a quadruple axel. It forces all the other competitors to perform the same high risk jump if they are to have any chance of winning. Most of them botch it, so they do worse than they would have otherwise.

But it has nothing to do with a lack of incentive, intimidation, distraction or anything else postulated by this article. It's the result of a rational high-risk strategy, given the circumstances.

This is an excellent point, and it seems testable. Are there any golf fans that have seen these variations the strategies the pros use?

Also of note I think is that in the last ten years or so only two golfers (Rich Beem in the PGA and Hal Sutton) have held Tiger off in the final round of a tournament when he had a legitimate chance. Both of these two golfers seem to have very laid back personalities on the course. Perhaps, that is what it might take along with a whole lot of talent.

I was at a talk on this paper the author (of the study) gave. She considered this possibility explicitly. Riskier play translates into a higher and more volatile score. In statistical terms this is higher variance. She found no evidence of that.

It would be interesting to see if their scores are in fact more volatile when Tiger is playing. Probably more interesting than actually watching golf.

Actually, a couple years ago the then Yankee Gary Sheffield said something to the affect of 'no one can strike me out if I don't want to be struck out.' A bunch of people jumped all over him for saying it, because although he doesn't strike out a lot compared to some power hitters, he does still strike out.

They assumed this meant that he was tanking it when he did. I scratched my head and wondered what everyone's problem was. In baseball, with the bases loaded, down by 3 runs, with two outs and two strikes, what is a hitter going to do? Say he plays it safe and just tries to make contact. He puts it in play and has maybe a .3 chance to reach base safely. He's now the winning run at first. The next hitter has a .3 chance to get a hit. And the next one has about the same chance. If they all get singles they game may still be tied. Meanwhile there is a .7 chance that the game will end with each at bat. When you multiply that all out, if your the sort of guy who can hit a game winning grand slam (and in the steroids era what player isn't?) maybe it's worth taking a rip at the ball instead of a cautious protect the plate swing. In golf, if your already down five strokes, it doesn't make much sense to play conservatively.

This is an explicit strategy in tournament bridge, where competing teams play exactly the same cards. Suppose you are in the last stages of a competition, and are near the top, but not actually leading. You can assume that the leaders will chose the course of play with the highest probability of success. If you choose the same strategy, whether or not it turns out to be correct, you will make the same score as the leaders and gain nothing. Therefore, to have a chance of winning, you must delibrately choose a strategy with a lower chance of success. Most of the time, this will not work, and you will lose ground to the leaders. However, part of the time the lower-probability strategy turns out to be the correct one. In that case, you score a large swing with respect to the leaders, and can possibly win.

Boomer

I obviously did not see the presentation, but my observation of golf tournaments suggests that riskier play shifts the curve down a lot more than up, and the players who succeed that way are outliers. Put differently, it changes the scores from something that looks like a normal bell curve to something that looks like bell curve with a little tiny extra tail added on the side of lower/better scores. It's not clear that they would create a statistically significant change in variance.

It also seems reasonable to me that playing more aggressive golf than you usually play is just a bad strategy and that it essentially gives everyone who tries it a worse score. In that case you wouldn't see an increase in variance. You might even see a decrease in variance if only the people who think they are within striking distance of Woods try to play that way, since their scores would decline while the scores of the middle-of-the-pack players would stay the same.

I also believe that the causal relationship is about managing risk. The analogy to figure skating and trying risky jumps to compete is bang on. The study found that the top competitoirs for Tiger Woods had higher scores when Tiger is in the field. The less competitive golfers did not suffer as much as the top competitors. Since the top ones had a chance to beat Tiger, they would have to take more risky shots to compete. The lower down golfers, knowing that they couldn't beat Tiger (and the other top golfers), would not take the risky shots. And as a result they were not as affected as the top golfers. The low golfers don't need to play "outside" of their capabalities. They didn't suffer the result of risky play.

I'd like to see a study that interviews all golfers to find out how they manage risk when playing Tiger.