Introduction  John
Paul Newport is the golf columnist for the Wall
Street Journal. He does well when
his column is purely descriptive (e.g., my round with Donald Trump), but
struggles when the subject is more technical.
His difficulty is exemplified by two columns where Newport extolled the
work of Mark Broadie and his “strokes gained statistic.”[1] Both columns make the same points, and both
promote Broadie’s forthcoming book, Every
Shot Counts. More problematic is why Newport is promoting a
book that is still “forthcoming” some 20 months after he first wrote about
it.
Both columns argue that Broadie’s work has debunked myths
about the determinants of scoring. If Newport
had a background in player performance research, he would have known that 1)
the myths listed in the column are straw men or myths that have been debunked a
long time ago, and 2) the putting myth may not have been debunked at all. If he had a technical background, he could
have challenged Broadie on some of the author’s findings. And finally, if Newport weren’t so
enthralled, or overwhelmed, by Broadie’s mathematics he could have examined the
value of Broadie’s research to the average golfer. Each of these shortcomings is examined in
turn.
Demystifying Broadie
Many of Broadie’s findings can be found in Cochran and Stubbs’ book, The Search for the Perfect Swing,[2]
hereinafter referred to as Cochran. In
fact, even the “strokes gained” nomenclature was first used by Cochran. Cochran studied 40 golfers at one tournament
at minimal cost. Broadie’s research tab
was probably in the millions of dollars when the cost of collecting the data is
added.
Myth #1  Driving
Accuracy is Important
Newport wrote that Broadie’s research has shown “driving contributes
28% of top player’s advantage, and the main factor there is raw distance, not
accuracy.”[3] Forty six years ago Cochran wrote “In fact,
putting it rather loosely, distance from the tee seems to count for more than
accuracy.”[4] So there was no myth about the primacy of accuracy
or if there was it was debunked in the last century.
Myth #2 Long Approach
shots are not that important.
Newport wrote “The biggest factor in lower scores, however,
is approach shot accuracy. It contributes 40% of the advantage that the Tour’s
top players enjoy over their peers…For Woods, by far the top strokesgained
player between 2004 and 2012, it was even more: 46%.”[5]
Of course, Cochran found the importance
of the long approach shot and even entitled a chapter “Long Approach
Shots—Where Tournaments are Won “ [6] Sorry, no myth debunked here.
Myth #3 – Lay up to a
good distance is better than getting it as close as possible.
Newport wrote that
Broadie concluded ”that laying up short to a green to a comfortable distance,
such as 100 yards doesn’t generally lead to better scores than knocking the
ball as close as possible.” [7]
This is consistent with Cochran’s finding that pros hit their half of their
approach shots between 7.5% and 8 percent of the range from which each stoke
was played . Moreover Cochran found that
the number of shots to get down from approaches of more than thirty yards from
the hole could be estimated by:[8]
Number
of shots to get down = .0044·d +2.35
Where ,
d = the
distance in yards.
Broadie reported a similar estimating equation:[9]
Number
of shots to get down = .0041·d + 2.38
In essence, both recognized the importance of getting close
except in certain circumstances.
Myth #4 –Putting is
not golf’s most crucial skill.
Newport wrote “The No. 1 shibboleth Broadie’s research debunks
is that putting is golf’s most crucial skill.”
Broadie and Cochran have a small disagreement here, but that could be
due to methodology or semantics (i.e., how “crucial” is defined). Cochran
looks at the proportion of putts holed from various distances for the top nine
and bottom nine finishers in the tournament studied. The top nine were more proficient than the
bottom nine at every distance. Cochran
estimates the top nine players gained (emphasis
added) 1.8 strokes per round over the bottom nine by better putting alone. Since the difference in scoring between these
two groups was 4 strokes, 45% of the difference was the result of putting. That is, putting was crucial in determining the tournament’s outcome.
Newport wrote that “Broadie finds that on average putting
contributes 35% of Tour winners’ advantage.” This is not far from Cochran’s estimate of
45%. Since Cochran’s comparison is with
the bottom finishers and Broadie’s comparison is with the average finisher, it
is likely that both would conclude putting contributes to approximately 35% of
a Tour winners’ advantage. Newport takes
this figure of 35% and implicitly concludes that putting cannot be that
important if 65% of a winner’s advantage is due to something else.[10] There are three problems with Newport’s
reasoning.
First, the largest contributor to a golfer’s success
depends on how you breakdown the components of scoring. Table 1 below shows the contributions
different shots make to Tiger Woods “strokes gained” statistic. From Table 1 you would conclude the two
biggest contributors to the success of Tiger Woods are driving and putting. You would not use Newport’s construct that
driving is not that important since it only contributes 22% of Wood’s total
strokes gained (i.e., the other parts of his game contribute 78%).
Table 1
Strokes Gained by Tiger Woods (20032010)[11]
Total

Long Tee

100150

150200

>200

020

20100

Sand

Putt

3.2

0.70

0.20

0.66

0.49

0.13

0.19

0.07

0.70

Second,, if a player does not gain strokes by putting, it
does not necessarily mean he putted poorly.
Let’s assume a three hole tournament.
Player A sinks 2 out of three putts from 10 feet. Player B sinks 1 out of three putts from 30
feet. Player A’s stroked gains putting
is .83, while Player B’s strokes gained putting is .94 strokes.[12] Player A wins the tournament, but comes in
second in the “strokes gained putting” statistic. Unlike Cochran, Broadie does not compare the
putting ability of players for the same type of putt. A player who hits par fives in two and
sticks his irons close, may not have an impressive “strokes gained putting”
statistic. This is not the same as
saying such players are not good putters.
Third, the importance
of putting in determining who wins may be due to its variability. Players typically drive the same distance
each week, but can have extraordinarily good and bad putting tournaments. Using Broadie’s 2010 data, there was
essentially no correlation between average “strokes gained putting” and money
winnings per tournament (see Appendix).
The PGA Tour has a nonlinear payoff, however, and a good putting week
can vault a player to the top and to a big pay check. Putting is clearly not the sole determinant
of who wins, but for many players it has been crucial.
Lack of Critical
Analysis – Newport fails to question anything that has a hint of
mathematics. Here are some examples:
What errors are
involved in Strokes Gained Analysis – It appears Broadie uses the same
benchmark for all courses on the Tour. This
could lead to errors. Assume putts are
tougher to make at a course because of the undulation and speed of a
green. A player hits an iron from 160
yards to 10feet of the flagstick. Now
from 160 yards the player is expected to complete the hole in 2.98 strokes. [13]
From 10feet Broadie estimates it would
take an additional 1.61 strokes.[14] Broadie would estimate the strokes gained
from the approach to be 0.37 strokes.
But what if the probability of making a 10foot put on this course were
1.81 strokes? In that case, the strokes
gained by the approach shot would be 0.17 strokes, not 0.37 strokes. If the putt was made, Broadie would estimate
the strokes gained by putting at .61 when it should be .81 strokes. Broadie does try to normalize the “total”
strokes gained. It is not apparent if
errors in the estimates of strokes gained by shot category are corrected.
Some Benchmarks Are a
Little Strange  Broadie estimates is takes 2.99 stokes to complete a
120yard hole if the ball is teed up.[15] He also estimates it takes only 2.85 strokes
to complete a hole from 120yards from the fairway. The advantage of playing
from the fairway vanishes at distances of 140yards or more. Broadie does not explain this anomaly. Broadie also estimates it would take 6.1
strokes to complete a hole if the player is in a sand bunker some 600 yards
from the hole. It is not clear on what
data set such an estimate could be made.
The Listing of the
Most Difficult Courses on the Tour Appears Biased Toward short Courses  TPCSawgrass and Harbour Town Golf Links are
listed as the first and third most difficult courses on the PGA Tour.[16] These are two of the shorter courses on the
Tour. Broadie’s methodology assumes both
courses play to their yardage (i.e., scores should be lower there reflecting the
short yardage). The “effective” playing
lengths of these courses, however, are much longer. The
increased effective length stems from the driver not being used on many holes
at these two courses. If the difference
between actual and effective length is 300 yards, Broadie would underestimate
the benchmark total score by 1.32 strokes (i.e., 300 yards·.0044). If the
effective yardage was used in the strokes gained analysis, the difficulty ranking
of each of these course drops considerably.
Usefulness to the
Average Golfer  If Broadie’s research was valuable to the average player,
Newport’s over promotion of the forthcoming book would be understandable as a
public service. Newport’s columns,
however, do not address how the average player would go about using the
findings. The promo for the Broadie’s
book claims “Broadie uses analytics to uncover the secrets of the game of
golf.” This is pure hyperbole. There are no secrets, and to imply that there
are is misleading at best. The publisher’s promo goes on to ask “What does it
take to drop ten strokes from your golf game?” and implies the answer lies
within the book covers. I suspect the
answer is the typical bromide – hit it longer, straighter, and improve around
the greens.
The real policy question that Newport avoids is this: A
player has limited money and time to invest in improving his game. What is the most costeffective use of those
resources? A player should be able to
spot his deficiencies without Broadie’s book.
When he plays with better players, he needs to note what part of his
game leads to higher scores than his playing companions. He may realize he does not hit it as far,
but also recognize increasing his distance is not in the cards because of his physical
limitations. Conventional wisdom says he
will see that his short game suffers in comparison. The better player does not skull his chips,
flail away in sand bunkers, or threeputt with regular frequency. Since short game skills are a matter of
technique rather than physical strength, concentrating on this part of the game
seems most costeffective use of an average golfer’s resources. Maybe Newport will have a third column that
debunks this conventional wisdom. Until
he does, a prospective reader should pass on Every shot Counts and save $24.92 (plus shipping and taxes). Remember, every dollar counts.
Appendix
Money Winning per Tournament versus
Strokes Gained Putting
Table A shows the strokes gained putting and average winning
per tournament for a sample of players. A
linear regression was performed with Money/Tournament as the dependent
variable, and Strokes Gained Putting as the independent variable. The estimated equation was:
Money/Tournament
= 91,000 +25,600 ·Strokes Gained Putting
R^{2} = .02
The coefficient of the Strokes Gained Putting variable was
not significant at the 95% level of confidence.
Table A
Strokes Gained
Putting and Money Winnings per Tournament for Selected Players
Name

Rank

Strokes Gained Putting

Money/Tournament

Donald, Luke

1

0.863

183,261.70

Casey, Paul

2

0.813

212,540.82

Petterson, Carl

3

0.813

66,705.69

Wilson, Dean

4

0.779

46,257.78

Chalmers, Greg

5

0.773

36,645.00

Gay, Brian

6

0.729

50,722.10

Goosen, Retief

7

0.674

169,373.11

Kuchar, Matt

8

0.638

188,864.50

Collins, Chad

9

0.625

31,383.12

Johnson, Zack

10

0.579

116,679.72

Wi, Charlie

11

0.565

58,092.30

Imada, Ryuji

12

0.554

36,745.32

Sim. Michael

13

0.520

66,946.30

Jones, Matt

14

0.511

45,027.52

McCarron, Scotrt

15

0.503

22,156.66

Merritt, Troy

16

0.503

27,137.14

Baddeley, Aaron

17

0.503

33,819.88

Na, Kevin

18

0.488

77,762.12

Molder. Bryce

19

0.475

54,939.92

Snedeker, Brandt

20

0.464

61,641.92

Westwood, Lee

21

0.458

309,086.73

Stricker, Steve

25

0.435

220,538.68

Furyk, Jim

31

0.402

229,029.62

Els, Ernie

43

0.330

227,943.05

Toms, David

53

0.263

63,639.92

Harrington, Padraig

54

0.260

76,747.39

Poulter, Ian

68

0.211

138,644.00

Fowler, Ricky

78

0.150

102,039.57

Duval, David

85

0.117

38,316.00

Johnson, Dustin

86

0.113

194,483.57

Choi, K.J.

98

0.054

99,998.27

Weir, Mike

114

0.018

29,425.89

Woods, Tiger

116

0.034

107,897.08

Appleby, Stuart

119

0.053

63,413.71

O'Hair, Sean

130

0.088

74,361.60

Mickelson, Phil

144

0.148

191,086.65

Cabrera, Angel

145

0.150

66,654.74

Sabbatini, Rory

155

0.200

59,492.62

Garcia, Sergio

174

0.368

62,456.33

Mediate, Rocco

191

0.550

45,522.68

Singh, Vijay

204

0.738

55,594.25

Scott, Adam

205

0.743

124,470.10

Mayfair, Billy

211

1.014

24,701.19

[1]
Newport John Paul, “The Short Game’s the Thing? Nope,” Wall Street Journal, June 8, 2012 and Newport, John Paul, “Research
Debunks Golf Myths,” Wall Street Journal,
January 16, 2014.
[2]
Cochran, Alastair and Stobbs John, The
Search for the Perfect Swing, The Bootlegger, Grass Valley, CA, Copyright
1968.
[3]
Newport, 2014.
[4]
Cochran, op. cit., p. 184
[5] Newport,
2014. Broadie reports the average
strokes gained from the long tee by the top ten players is .61 strokes. The average strokes gained by these groups is
1.84 strokes. The advantage due to
driving would then be 33% of the total not 28%.
The difference could be due to a different time frame. In his article “Assessing Golfer Performance
on the PGA Tour” Broadie uses data from 20032010, and not 20042012. Interestingly, Broadie reports different
numbers in two different papers. In “Putts
Gained: Measuring Putting on the PGA Tour” Tiger Woods in ranked 116^{th}
in putts gained for the year 2010. Tiger
Woods was ranked 91^{st} in 2010 in his paper “Assessing Golf Performance on
the PGA Tour.”
[6]
Cochran, op. cit., pp. 196202.
[7]
Newport, 2014.
[8]
Cochran, op. cit., p. 198.
[9]
Broadie, Mark, “Assessing Golfer Performance on the PGA Tour,” Columbia
University, 2011, p. 8.
[10]
Newport, 2014. Newport writes “65% of a
winner’s advantage comes from off the green.”
[11]
Broadie, Assessing Performance, , p. 18.
[12]
Broadie, Mark, “Strokes Gained, Measuring Putting on the PGA”, Columbia
University, 2011, p.4.
[13]
Broadie, Assessing Performance, p.31.
[14]
Broadie, Strokes Gained, p.4.
[15] Broadie,
Assessing Performance, p. 31.
[16]
Broadie, Assessing Performance, p.26..
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