1. Skill and Randomness on the PGA Tour Roland Minton Roanoke College

2. Skill or Randomness?
“One necessary (but not sufficient) sign of a good statistic is that
whatever it measures is somewhat repeatable; if it’s not repeatable,
then it’s probably random, and if it’s random, then we don’t really
care about it.” Rob Vollman et al Stat Shot
On baseball fielding statistic UZR varying: “It is an unreliable
predictor of future performance.”
Baumer/Zimbalist The Sabermetric Revolution
Not repeatable implies bad stat or not a skill.
Corollaries: Winning close games is luck.
Clutch players do not exist. .
Question: How do golf statistics stack up?

3. Strokes Gained
The new standard in golf statistics is Strokes Gained. Quickly, …
420-yard par 4. Average score by PGA Tour golfers:
Tee shot: in fairway, 150 yards from hole. Average score: 3.96
Approach shot: on green 15 feet away. Average score:
Putting: 2 putts
Strokes Gained par 4 tee shot:
Strokes Gained fairway :
Strokes Gained putting:
ShotLink measures all shots on the PGA Tour to the inch.

4. Strokes Gained Categories
Putting
Fringe
Greenside Bunker
Fairway 0-50, , , ,
Intermediate Rough 0-50, ,
Primary Rough 0-50,
Miscellaneous 0-50,
Layup
Recovery
Penalty
Tee shots par 3, par 4, par 5
See

5. Strokes Gained Categories
Putting
Fringe
Greenside Bunker
Fairway 0-50, , , ,
Intermediate Rough 0-50, ,
Primary Rough 0-50,
Miscellaneous 0-50,
Layup
Recovery
Penalty
Tee shots par 3, par 4, par 5
See

6. Autocorrelation Tee 4 Putt Fairway Tee 3
Years , top 250 in ShotLink data set
~ 2000 instances of consecutive player-years
Correlation of year n stats to year n+1 stats
Tee 4
Putt
Fairway
Tee 3

7. Autocorrelation 1-6’ 7-12’ 13-22’ 23-32’ >48’ 33-48’
Years , top 250 in ShotLink data set
~ 2000 instances of consecutive player-years
Correlation of year n stats to year n+1 stats
1-6’
7-12’
13-22’
>48’
33-48’
23-32’

8. More Correlations Years 2005-2015, top 250 in ShotLink data set
Correlation of stats in same year
Strokes Gained putting 8’ to
Strokes Gained putting other distances
Strokes Gained putting 3’ to
Strokes Gained putting other distances
Strokes Gained fairway 150 yards to
Strokes Gained fairway other distances
Strokes Gained fairway 180 yards to
Strokes Gained fairway other distances
Strokes Gained par 5 tee shots 550 yards
Strokes Gained par 5 tee shots other distances
Strokes Gained par 3 tee shots 180 yards
Strokes Gained par 3 tee shots other distances
Strokes Gained par 4 tee shots 450 yards
Strokes Gained par 4 tee shots other distances

9. No Skill in Golf?

10. No Skill in Golf?
Strokes Gained does measure performance on a given shot.
My “average” for comparison is based only on distance, lie.
The standard of the average PGA Tour pro is exacting.
Performance in golf has a large noise component.
Bill James Underestimating the Fog.
Selection bias? Players who have a bad year one year
are not likely to be in the data set the next.
Some players have consistent strengths and weaknesses.
Most on the PGA Tour do not.
Short putting and driving are the shot types that are the
most consistent from year to year.

11. Any Questions? minton@roanoke.edu