Gdula's Golf Simulations: Waste Management Phoenix Open
Volatility is the name of the game in golf, and picking winners isn't easy. With fields of 150-plus golfers sometimes being separated by how a putt or two falls each week, predicting golf can be absurdly tough.
We'll never be able to capture everything that goes into a golfer's expectations for a week, but we can try to account for that by simulating out the weekend and seeing what happens.
The Process
Over the years, I have made plenty of tweaks to my original golf model, which uses a combination of the OWGR's field strength numbers and datagolf's field strength numbers to adjust each golfer's score relative to the field (on the PGA Tour, the European Tour, and the Korn Ferry Tour).
The ultimate goal is to place a score from the Waste Management Open, the BMW International Open, and the Knoxville Open on level playing fields. This adjusted strokes metric lets me see how golfers are performing across all tours. From there, a golfer's adjusted stroke data is combined with their round-to-round variance to see how the field is likely to perform when playing out the event thousands of times.
In addition to that long-term adjusted form, I factor in course-level adjustments for course fit.
I run a second model that uses more granular strokes gained data, which allows me to adjust for course fit very easily. The results are averaged out.
I let the data do the talking and don't make many tweaks. Golfers with a small sample get regressed to a low-end PGA Tour player to round out their samples.
Here are the most likely winners for the Waste Management Phoenix Open, according to the model.
| Golfer | Simulated Win% |
Simulated Top-10% |
Simulated Made Cut% |
FanDuel Sportsbook Win Odds |
|---|---|---|---|---|
| Jon Rahm | 9.7% | 49.3% | 90.9% | +650 |
| Justin Thomas | 8.6% | 45.6% | 89.4% | +800 |
| Xander Schauffele | 8.0% | 43.9% | 88.6% | +1000 |
| Rory McIlroy | 5.8% | 35.0% | 83.4% | +1000 |
| Daniel Berger | 4.5% | 35.8% | 86.3% | +2000 |
| Webb Simpson | 4.0% | 31.9% | 84.7% | +1600 |
| Harris English | 3.5% | 29.9% | 81.3% | +2700 |
| Russell Henley | 2.3% | 24.8% | 79.1% | +5000 |
| Hideki Matsuyama | 2.2% | 17.9% | 72.7% | +2000 |
| Scottie Scheffler | 2.1% | 20.0% | 73.8% | +4100 |
| Ryan Palmer | 2.0% | 18.9% | 72.8% | +4500 |
| Bubba Watson | 1.9% | 19.7% | 74.4% | +4200 |
| Will Zalatoris | 1.6% | 19.3% | 75.9% | +3400 |
| Sungjae Im | 1.5% | 15.0% | 70.9% | +2900 |
| Brooks Koepka | 1.4% | 14.5% | 68.7% | +4500 |
| Billy Horschel | 1.3% | 15.5% | 70.0% | +5500 |
| Matthew Wolff | 1.3% | 13.1% | 64.4% | +4500 |
| Siwoo Kim | 1.3% | 13.8% | 65.9% | +5500 |
| Sam Burns | 1.3% | 15.7% | 69.8% | +6500 |
| Jason Day | 1.3% | 15.1% | 69.8% | +5500 |
| Corey Conners | 1.2% | 14.4% | 69.7% | +7000 |
| Louis Oosthuizen | 1.1% | 12.7% | 66.3% | +5000 |
| Brendon Todd | 1.0% | 12.6% | 67.4% | +10000 |
| Rickie Fowler | 1.0% | 10.8% | 63.7% | +4100 |
| Brian Harman | 0.9% | 12.1% | 69.1% | +8000 |
| Gary Woodland | 0.8% | 9.0% | 61.6% | +5000 |
| Joel Dahmen | 0.8% | 11.4% | 62.5% | +15000 |
| Matt Kuchar | 0.8% | 10.9% | 64.7% | +8000 |
| Brendan Steele | 0.8% | 9.4% | 60.2% | +6500 |
| Talor Gooch | 0.8% | 11.7% | 64.8% | +10000 |
| Kevin Streelman | 0.7% | 11.2% | 63.1% | +19000 |
| Max Homa | 0.7% | 7.7% | 57.2% | +7000 |
| Harold Varner III | 0.7% | 11.1% | 63.7% | +15000 |
| Carlos Ortiz | 0.7% | 8.5% | 61.8% | +7000 |
| Charley Hoffman | 0.6% | 9.4% | 61.9% | +15000 |
| Henrik Norlander | 0.6% | 7.8% | 60.4% | +8000 |
| Erik van Rooyen | 0.6% | 10.1% | 63.6% | +15000 |
| Zach Johnson | 0.6% | 9.0% | 62.8% | +12000 |
| John Huh | 0.5% | 8.3% | 63.2% | +12000 |
| Cameron Champ | 0.5% | 6.4% | 55.7% | +8000 |
| Sepp Straka | 0.5% | 8.0% | 58.3% | +12000 |
| Sebastian Munoz | 0.5% | 7.1% | 58.0% | +12000 |
| Ryan Moore | 0.5% | 6.9% | 55.9% | +12000 |
| Chris Kirk | 0.5% | 6.6% | 60.0% | +10000 |
| Byeong Hun An | 0.5% | 4.7% | 49.9% | +9000 |
| Adam Hadwin | 0.5% | 6.8% | 56.4% | +10000 |
| Rory Sabbatini | 0.5% | 7.5% | 59.3% | +10000 |
| Adam Long | 0.5% | 6.1% | 56.0% | +12000 |
| Patton Kizzire | 0.5% | 6.1% | 54.9% | +12000 |
Jon Rahm excels at TPC Scottsdale and has posted four straight top-16 finishes. He enters with elite form and the right stats to fare well again, but the odds are super short for a field of more than 130 golfers. He'd need to have win odds of around 13.3% to have a break-even expected value, so I'll look elsewhere.
The same applies to the other guys at +1000 or shorter: Justin Thomas, Xander Schauffele, and Rory McIlroy. Just not enough value based on my simulations to want to start the card there.
The more appropriate value emerges a tier below: Daniel Berger, Harris English, Scottie Scheffler, Ryan Palmer, Bubba Watson, and Russell Henley, with Henley rating as the best value overall. But it's a tight, tight field. The top six golfers comprise 40.5% of the expected wins, so we should probably keep the long shots in check. Prior winners here -- Webb Simpson, Rickie Fowler, Gary Woodland, Hideki Matsuyama (twice), Brooks Koepka -- are generally the studs.
My bets so far include outrights on Berger and Watson and top-10s on Corey Conners, Talor Gooch, Ryan Moore and Russell Henley.
