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Tag Archives: course fit

Torrey Pines Preview – 2015

Dual course event this week, but Torrey Pines South will be used for three of the four rounds. Torrey Pines North is a much easier venue – by around three strokes/round – largely because it’s almost 600 yards shorter at the same par 72. The par 5s are all scoring holes – unlike at the sister course to the south.

Torrey Pines South is a stiffer test. It’s the longest course the Tour visits in scorecard length, and it plays as one of the longest if you look at average approach shot distance. It’s particularly long when you focus just on par 4 length (only Valhalla (PGA Championship) and PGA National (Honda) challenged it last year). The rough is nasty here; it played nearly the most difficult on Tour last year.

This is a course that requires the game that most elite players possess – long enough to score on the long par 4s and par 5s, accurate enough to not live in the rough, and good with the mid and long irons that almost every hole requires.

What I’m Watching For:
Jordan Spieth has been the best golfer in the world since October (minimum 16 rounds), with wins in Australia and at Tiger’s event and a back-door top ten in Phoenix last week. Spieth started last season hotter than just about anyone, but fell off towards the summer because he completely lost his game off the tee. In 2013, he combined above-average distance with nearly the most accurate tee shot on Tour and ranked in the top ten in performance on drives. Beginning at some point last spring/summer, he started spraying it everywhere off the tee, costing him a huge amount of his advantage on drives. It’s only one tournament of data, but last week he was great off the tee – gaining about a stroke/round on drives and hitting it as straight as in 2013.

top ten since october

Shane Lowry making a rare US start this week. He’s a guy most PGA Tour fans won’t be that familiar with, but last year was his first big year on the European Tour. He started off ridiculously cold missing six of eight cuts, but contended all the way in the European flagship event in May. From May onward he played at the level of a top 20 golfer in the world and hasn’t missed a cut since June. No clue how Lowry will do in his first start at Torrey Pines, but he’s a legitimate contender in this field at the level of Harris English or Marc Leishman.

Best Long Course Golfers:
These numbers are illustrative only, but these are the best and worst on long courses since 2010. Long courses are the top 25% of PGA Tour courses in average approach shot length (these include Torrey Pines South, PGA National, & Congressional) and this is performance with putting removed. I’ve compared performance on long courses to performance in all others rounds. The 219 golfer sample yielded 19 golfers with statistically significantly different performances (negative z-scores below indicate better performances on long courses).

differences on long vs short coursesOn the positive end, Keegan Bradley and Kyle Stanley  are the most notable to play much better on long courses. On the negative end, Tim Clark and J.B. Holmes struggled the most on long courses.

Doing the reverse analysis and measuring performance differences on the shortest 25% of courses reveals some of the same names. Graham DeLaet and Kevin Na stuggle most notably on shorter tracks, while Jason Day stands out as by far the most extreme in favor of short courses.

Now, those numbers just use aggregate performance on all strokes and are surely distorted by all kinds of random variation. However, it makes sense that golfers who play better on longer courses would hit their long irons better, while those who are better on short courses hit their wedges better. Looking deeper at shot-by-shot stats over the past year, DeLaet, Stanley, and Bradley all hit their mid to long irons much better than their wedges, while Tim Clark and Jason Day both have huge splits in favor of hitting their wedges better. The only player whose stats don’t back up his performance is J.B. Holmes.

Best Course History:
These are the guys who have played best here relative to their typical performances. In other words, for each year they’ve played I’m comparing their Torrey Pines performance to their average performance for the year (minimum 4 starts here since 2008 including the US Open).

1. Lucas Glover
2. Jhonattan Vegas
3. Tom Gillis
4. Justin Leonard
5. Marc Leishman
6. Bill Haas
7. Brendan Steele
8. Brandt Snedeker
9. Stewart Cink
10. D.A. Points

Is Going Low a Skill?

Winning a PGA Tour tournament normally requires besting the field average by 12-15 strokes. However, Tour courses vary widely in difficulty between the US Open tracks which normally play several strokes over par and the easier resort style courses which can play several strokes under par. On the former, winning scores hover around par, while on the latter it often takes -25 under par to win the tournament. On difficult courses making mostly pars puts you in contention, while on easy courses a golfer needs to make a lot of birdies to even have a chance. What I was interested in is whether certain types of golfers perform better on difficult or easy courses. That is, are golfers who make more birdies than the field better set to tackle courses where you have to go low? And are golfers whose games are built on avoiding bogeys a better bet on hard courses where you have to grind for par? My research showed that there was a small affect in each direction, but one that doesn’t significantly impact most golfers’ results.

To set-up my study I collected the results for every golfer who played a qualifying number of rounds on the PGA Tour in 2013 and 2014 (~360 golfer seasons). I then adjusted their rates of birdie holes and bogey holes to account for the courses they played each season. In most cases the adjustments weren’t significant, but the better golfers tend to play harder courses and the worse golfers tend to play easier courses (there is positive relationship between the prestige of the tournament and the difficulty of the course). That yielded a relative birdie% and relative bogey% for each golfer. By subtracting bogey% from birdie%, you can find how dependent each golfer is on making birdies versus avoiding bogey for their scoring.

Last year, Rory McIlroy ranked 1st in birdie% and 4th in bogey%; he was more dependent on making birdies for his scoring. Jim Furyk ranked 39th in birdie% and 1st in bogey%; he was more dependent on avoiding bogeys for his scoring. I divided every golfer into one of six groups depending on how dependent they were on making birdies or avoiding bogeys. I’ll refer to those dependent on making birdies as Birdie Generators and those dependent on avoiding bogeys as Bogey Avoiders.

I then gathered the course specific scoring averages for each event, adjusted them by the quality of the field, and compared them to each courses’ par. For example, at the Sony Open in 2014 the field averaged 69.3, the field was 0.3 strokes worse than PGA Tour average, and the course par was 70. Adding all that together, an average field would have played that course in 1 strokes under par (70-(69.3-0.3)). For the 2014 Masters, the field averaged 73.95, the field was -0.3 strokes better than PGA Tour average, and the course par was 72. An average field would have played that course in 2.2 strokes over par (72-(73.95+0.3)). I then divided those courses into four groups based on their average difficulty; Easiest (>1 stroke under par), Easy (0-1 stroke under par), Hard (0-1 stroke over par), and Hardest (>1 stroke over par).

bogey vs birdie course fit study

Read the chart with more negative values indicating better performance. The “Difference” column indicates the difference between performance on the easiest courses and hardest courses. Negative values indicate golfers in that group performed better on the easiest courses.

The results indicate that the most extreme Bogey Avoiders perform almost 0.2 strokes worse on the easiest courses relative to the hardest courses. The most extreme Birdie Generators don’t display the reverse, but with only eleven golfers, those results may reflect randomness because the next two less extreme groups of Birdie Generators definitely perform better on the easiest courses.

However, the results also indicate these values are not impacting tournament results for most golfers. Perhaps the most extreme Bogey Avoiders should be downgraded slightly on the easiest courses (like at the Humana this week), while it looks like the Birdie Generators definitely do play slightly better on easy courses and slightly worse on hard courses. However, even for the most extreme golfers, playing an unfavorable courses is only worth between 0.1 and 0.2 strokes different from their regular performance – enough to shift the odds of winning by around 1% for the best golfers and by much smaller fractions for lesser golfers. Going low is a skill, but it only makes a very small impact on real-world results.