Gdula’s Golf Simulations: WGC-Workday Championship
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 — if any. Golfers with a small sample get regressed to a low-end PGA Tour player to round out their samples. Data points are weighted more heavily toward recent performance.
Here are the most likely winners for the WGC-Workday Championship, according to the models.
| Golfer | Simulated
Win% |
Simulated
Top-10% |
FanDuel
Sportsbook Win Odds |
|---|---|---|---|
| Dustin Johnson | 9.8% | 49.0% | +600 |
| Xander Schauffele | 7.8% | 46.5% | +1400 |
| Jon Rahm | 7.1% | 43.6% | +850 |
| Bryson DeChambeau | 6.2% | 42.2% | +2000 |
| Justin Thomas | 5.7% | 39.5% | +1800 |
| Daniel Berger | 4.4% | 37.3% | +3100 |
| Patrick Cantlay | 4.4% | 33.1% | +1800 |
| Rory McIlroy | 3.7% | 28.4% | +1600 |
| Tyrrell Hatton | 3.2% | 31.5% | +1800 |
| Tony Finau | 2.9% | 26.8% | +2000 |
| Patrick Reed | 2.6% | 27.8% | +3100 |
| Viktor Hovland | 2.6% | 23.8% | +2200 |
| Harris English | 2.5% | 27.8% | +5500 |
| Webb Simpson | 2.3% | 26.7% | +2900 |
| Collin Morikawa | 2.1% | 23.0% | +3400 |
| Joaquin Niemann | 1.9% | 19.4% | +4500 |
| Scottie Scheffler | 1.8% | 18.8% | +4100 |
| Matthew Fitzpatrick | 1.7% | 20.6% | +5000 |
| Brooks Koepka | 1.5% | 15.2% | +2700 |
| Will Zalatoris | 1.4% | 16.9% | +5500 |
| Hideki Matsuyama | 1.4% | 16.9% | +5000 |
| Adam Scott | 1.3% | 14.8% | +5000 |
| Abraham Ancer | 1.3% | 17.2% | +10000 |
| Ryan Palmer | 1.2% | 18.5% | +8000 |
| Kevin Kisner | 1.1% | 17.5% | +12000 |
| Bubba Watson | 1.0% | 13.1% | +8000 |
| Jason Kokrak | 0.9% | 13.3% | +9000 |
| Sungjae Im | 0.9% | 15.3% | +3300 |
| Sergio Garcia | 0.9% | 12.1% | +8000 |
| Mackenzie Hughes | 0.9% | 13.5% | +15000 |
| Cameron Smith | 0.8% | 12.2% | +4500 |
| Brendon Todd | 0.8% | 12.9% | +15000 |
| Lanto Griffin | 0.8% | 11.9% | +12000 |
| Kevin Na | 0.8% | 11.8% | +10000 |
| Billy Horschel | 0.8% | 13.7% | +10000 |
| Louis Oosthuizen | 0.8% | 13.0% | +6000 |
| Carlos Ortiz | 0.7% | 10.4% | +9000 |
| Matthew Wolff | 0.7% | 11.2% | +8000 |
| Tommy Fleetwood | 0.6% | 11.2% | +4100 |
| Jason Day | 0.6% | 12.0% | +5000 |
| Matt Kuchar | 0.6% | 9.0% | +15000 |
| Christiaan Bezuidenhout | 0.6% | 11.7% | +9000 |
| Max Homa | 0.5% | 8.2% | +5000 |
| Gary Woodland | 0.5% | 7.9% | +12000 |
| Shane Lowry | 0.4% | 9.5% | +7000 |
| Erik van Rooyen | 0.4% | 8.9% | +15000 |
| Marc Leishman | 0.4% | 3.8% | +8000 |
| Sebastian Munoz | 0.3% | 6.8% | +21000 |
| Justin Rose | 0.3% | 8.0% | +5500 |
| Lee Westwood | 0.3% | 8.5% | +12000 |
| Bernd Wiesberger | 0.3% | 6.4% | +12000 |
| Cameron Champ | 0.2% | 4.7% | +15000 |
| Lucas Herbert | 0.2% | 6.0% | +15000 |
| Rasmus Hojgaard | 0.1% | 3.0% | +10000 |
| Andy Sullivan | 0.1% | 3.5% | +12000 |
| Robert MacIntyre | 0.1% | 3.7% | +9000 |
| Thomas Detry | 0.1% | 2.3% | +15000 |
| Chan Kim | 0.1% | 2.4% | +32000 |
| Victor Perez | 0.1% | 3.0% | +9000 |
| Laurie Canter | 0.1% | 2.3% | +15000 |
| Rafa Cabrera Bello | 0.1% | 2.6% | +15000 |
| David Lipsky | 0.1% | 1.7% | +21000 |
| Aaron Rai | 0.1% | 1.8% | +27000 |
| Sami Valimaki | 0.0% | 1.9% | +21000 |
| Jason Scrivener | 0.0% | 1.5% | +27000 |
| Wade Ormsby | 0.0% | 0.4% | +50000 |
| Min Woo Lee | 0.0% | 0.1% | +42000 |
| Trevor Simsby | 0.0% | 0.0% | +50000 |
| Yuki Inamori | 0.0% | 0.0% | +42000 |
| Brad Kennedy | 0.0% | 0.0% | +50000 |
| Danie Van Tonder | 0.0% | 0.0% | +50000 |
| JC Ritchie | 0.0% | 0.0% | +50000 |
I didn’t make any empirical course adjustments for this week because, well, how could I? The Concession hasn’t ever hosted a PGA Tour event but did host the 2015 Men’s and Women’s NCAA championship. Bryson DeChambeau won the 2015 individual event shooting -8. Other golfers who played there and are in this field include Thomas Detry (finished 3rd), Jon Rahm (22nd), Scottie Scheffler (33rd), and Xander Schauffele (45th).
With Dustin Johnson sucking up a lot of of the win equity at +600, it actually opens up value for us because the models don’t think his win odds are that high (+600 is around 14.3%). Rahm is also overvalued at +850 (which means around 10.5% win odds), per the models.
That makes Schauffele, DeChambeau, Justin Thomas, and Daniel Berger positive values. Schauffele and Thomas are no-cut studs, as well.
Down-the-card values, per the model, include Harris English (+5500), Ryan Palmer (+8000), Abraham Ancer (+10000), and Kevin Kisner (+12000).
Just keep the long shots in check. The past winners at WGC events have been: Justin Thomas, Patrick Reed, Rory McIlroy, Brooks Koepka, and Dustin Johnson.
I’ll update this with my picks closer to Thursday.
