The research that led to this book began more than 10 years ago. What were you were trying to understand then? And why did you find traditional golf statistics inadequate to help you?
The traditional stats just couldn’t come close to answering what I thought were some pretty simple, interesting and fundamental questions about the game of golf. I was trying to understand questions like, where do the 10 strokes that separate a golfer who shoots 90 from a golfer who shoots 80 come from? We know that pros are better than amateurs at every type of shot, but how much does each type contribute to the difference in scores?
Golf is a game of different skills. You have to be able to hit the ball off of different surfaces — the grass, when it’s sitting up on a tee, the sand. Then putting is a game of feel and touch and green reading. They require different types of skills — which I think makes golf, in a way, more interesting than some other games played on a fixed court. But it wasn’t clear to me how much of each type of shot or each different skill contributed to scoring differences between different levels of golfers.
Another motivation was just trying to figure out, if I could hit the ball 20 yards farther, how much would my score go down? That seems like an easy question. Yet traditional stats, like fairways hit, greens in regulation, and putts per round, are just not helpful in answering it.
A tee shot counts as a “fairway hit” if you hit the ball and it finishes in the fairway. It doesn’t distinguish between a pop up that travels 100 yards or a 300-yard drive right down the middle. Both count as a fairway hit even though one shot is much better than the other. If you miss a green in regulation, the statistic doesn’t tell you why. It could be that you hit a poor drive, a poor approach, or both. Counting putts is almost ridiculous when a tapping it in from two feet away counts the same as holing out from 60 feet. Clearly, they reflect different performances in putting.
Do you see a similar problem in business?
Certainly. Performance measurement, be it at the individual or the group level, can be an important challenge in business. It can be extremely difficult to wade through, and control for, the many factors that affect performance. Sales can increase because of the effort of the marketing department or they can increase because a competitor drops out of the market. When you’re evaluating the marketing department’s performance, it’s important to understand those factors. So while this book describes how to better measure golf performance by controlling for the difficulty of a shot or putt, these ideas have wider applicability to performance measurement in business.
What's the business equivalent of putts per round—or a performance statistic that isn’t informative enough?
Investment returns are one. They’re usually easily observable — you know when you’re seeing gains. But for future investment decisions it’s important to know if good performance should be attributed to timing or security selection, to taking more risk or using more leverage, to skill or luck. In a golf tournament, we can see who had the lowest score and won the tournament, but we can’t easily see which areas of his game (for example, putting versus iron shots) contributed the most to the victory. We can’t always learn that much from success.
While you were working on this golf project, the PGA Tour put out ShotLink, which records every shot the pros hit in tournaments. How did that impact your work?
That was a fortuitous confluence of events. While I was writing this program for tracking amateur data called Golfmetrics, which in hindsight is like a personal ShotLink system, the PGA Tour was developing a much more extensive approach to collecting the same kind of shot level data from PGA Tour golfers at every tournament they play. Those two things together gave me a database of amateur and professional golf shots that I could use to answer the fundamental questions I mentioned about the game.
So from all this data, you came up with the statistic strokes gained. What is it and how can it be used?
As I describe in the book, in golf, rather than measuring your progress by how far you’ve hit the ball on a hole, it’s more valuable to look at the decrease in the average strokes it will take you to finish a hole from where you are. When you go from one shot to the next, how much have you lowered that average score? That’s what strokes gained shows.
This is valuable because you can use it to figure out where your individual strengths and weaknesses are. If you’re whose average score is 90, and you can focus on developing a better long game or short game, this information can help you figure out which would lower your score the most. From this stat, we can tell, for example, that the answer is generally the long game and your score would go down by about 6.5 strokes. Of course, golfers come in all shapes and sizes, and everybody’s a little bit different.
In the book, you describe how amateur golfers often focus too much on their emotions when making choices on the course. But is there a place for emotion in decision making?
The whole area of golf decision making, I think, is pretty interesting. I don’t think any of the statistics I’m describing would replace the human element of that decision making process. If there’s a choice between two shots and one shot you feel confident and comfortable and the other shot you feel hesitant and afraid, well . . . we know how that’s going to end up. If the numbers say doing one versus the other is going to, in the long run, save you 1/10th of a stroke, that doesn’t necessarily outweigh how you’re feeling about it. You’ve got to have some confidence in order to put a good swing on the ball.
What is it about golf that explains its long association with business?
One of the fun things about golf is that most everybody can play. You can even play on the same courses that the professionals play. Whereas most people my age, or within 20 years of my age, no longer play baseball or basketball or certainly not football, the fact that you can both watch these golf pros and also participate yourself, I think, is attractive for many people.
For business people, there’s also this notion that it’s a game of integrity. When you golf in a foursome — and maybe it’s a salesperson and potential clients or businessmen and potential customers — you get a better sense of what their personalities are and how they react to different situations — both how they celebrate and how they react under stress. It can be a revealing introduction.
Mark Broadie is the Carson Family Professor of Business, vice dean for curriculum and instruction, and an academic advisory board member for the Program for Financial Studies.
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Professor Broadie currently teaches the elective courses Security Pricing: Models and Computation, Computational Finance, and Programming for Business Research. He is an Academic Advisory...Read more.