I.T.N. No. 10
PUBLISHED July 8, 2019
Inside The Numbers ...
is a brief numerical summary of the current happenings in the world golf, published every Monday — hopefully.
29% TOP 5 RATE
Jon Rahm's career to-date has been better than nearly any of his contemporaries:

Rahm has picked up top 5s on the PGA Tour at a 29% clip in his first 69 starts, just shy of Tiger's mark of 35% through the same number of PGA Tour starts (including those he made as an amateur). When Rahm's career is placed alongside those of Tiger and Phil (you may need to squint to see his yellow line below), it's clear who the group's misfit is.
Victor Hovland has been impressive in the professional starts he has made so far in 2019, averaging +1.1 true strokes-gained in 28 rounds. Even more impressive is how he has gained those strokes: Hovland has averaged +1.1 SG:OTT and +0.9 SG:APP in this stretch, while losing about 0.6 strokes on and around the greens (note that these don’t quite add up because Hovland played at The Masters, where the strokes-gained categories are not tracked). Due to the fact that ball-striking performance is more predictive than short game performance, our predicted skill level for Hovland is 0.26 strokes higher if we incorporate the strokes-gained categories than if we don’t. Thus, despite the small sample size, Hovland's long game performance has placed him among the favourites at this week’s John Deere Classic.
Since Martin Kaymer started playing a full schedule on the European Tour in 2007, he has had just one season where his true strokes-gained average was below 0 — that being the 2018 season (-0.26). However, Kaymer’s career has not been immune to the occasional performance valley: Before a great run of form in 2016 and early 2017 where he approached the performance level of a top 5 player in the world, Kaymer was performing right around the level of an average PGA Tour player. The 2019 season has also seen a resurgent Martin Kaymer, and if his career to this point is any indication, this recent form might be here to stay for a while.
Dawson Armstrong won last week’s Windsor Championship on the Mackenzie Tour — a performance we estimated was worth +0.08 true strokes-gained per round. This performance would have been roughly equivalent to finishing T18, T46, or T58 at last week’s LECOM Health Challenge, Irish Open, and 3M Open, respectively.
Collin Morikawa has registered just 26 rounds in our historical database, but apparently that is enough for the model to make him the favourite at this week's John Deere Classic. Like Viktor Hovland, Morikawa has not only played well, but he has done most of the work with his long game. Therefore, while the model is applying substantial regression to the mean to Morikawa's small sample of (very) good performances, it is applying less than it otherwise would if Morikawa's performance was driven by his short game and putting.