Introduction
Errors in estimating the course and
slope rating can lessen the equity of competition between players from
different clubs. Players will have
either more or less handicap strokes than they deserve because of these errors. The complexity of estimating these ratings,
however, makes it difficult for the player to assess their accuracy.
This paper presents two simple
methods a player can use to assess the accuracy (reasonableness might be a
better word) of golf course ratings. The
methods are based only on knowing the course yardage, course rating, and slope
rating of the courses under consideration.
The first method calculates the
Obstacle Stroke Values (the subjective judgment on the difficulty presented by
obstacles such as rough and water hazards) for courses. The player can then use his own judgment on
whether the relative size of these values is consistent with his own playing
experience.
Second, courses are ranked by their
Obstacle Stroke Values for women and compared with a similar ranking for the
men. In Southern California these
rankings are done by different organizations, and can serve as a rough check
against each other. The rankings should
be similar though the placement of tees (e.g., women's tees are placed in front
of potential hazards) could explain any disparity. Major differences in rankings, however, may
be evidence of an error in the ratings (men's or women's).
While neither of these methods can
definitively pinpoint errors, taken together they can provide evidence on
whether a course is over or underrated.
Obstacle Values
Course and Bogey Ratings consist of
two components. The first component
measures the effect of course yardage on the ratings. The second component measures difficulty
factors such as rough, topography, water hazards, out-of-bounds, etc. This second component is called the Obstacle
Stroke Value and represents the increase or decrease in course rating due to
difficulty factors.
Estimating these Obstacle Stroke
Values is a subjective process. A final step in establishing a course rating is
to make sure that the proposed rating for a course is consistent with other
courses. For example, the Ratings
Committee will check the proposed rating against courses which are similar in
nature. A discrepancy in the comparisons
is then a call for further review.
One way to check on your course
rating, then, is to see if the Obstacle Stroke Values are consistent with other
courses you play.
Let’s look at the
women’s ratings at a number of courses in Southern California as an
example.
The Obstacle Stroke Values for these
courses were calculated,
and are shown in Table 1.
Using Table 1, a player can judge
whether the estimates of Obstacle Stroke Values correspond with her own playing
experience. For example, does she believe
that obstacle factors should make SeaCliff play 1.1 strokes higher than Mesa
Verde for the scratch player? Does she
believe Table 1 expresses the correct rank order of obstacle difficulty from
SeaCliff being the toughest to Dove Canyon being the easiest? Obviously opinions will vary, but if a
consensus differs from the ranking presented in Table 1 there may be cause for
reexamining some ratings.
Table 1
Obstacle Values for
Women's Rating
Course
|
Scratch Obstacle
Value
|
Bogey Obstacle
Value
|
SeaCliff
|
1.9
|
4.2
|
Coto de Caza
|
1.7
|
6.7
|
Mission Viejo
|
1.4
|
4.1
|
Santa Ana
|
1.0
|
3.0
|
Big Canyon
|
1.0
|
2.8
|
Mesa Verde
|
0.8
|
3.6
|
Newport Beach
|
0.7
|
2.2
|
Old Ranch
|
0.7
|
3.3
|
El Niguel
|
0.6
|
1.6
|
Dove Canyon
|
-0.8
|
0.8
|
Another approach is to use Table 1
to look for anomalies. Coto de Caza, for
example, has an unusually large Bogey Obstacle Value (6.7 strokes). What is more unusual is that the Obstacle Value
for women from the White Tees (700 yards longer) is lower (5.9 strokes) than
from the Red Tees. Typically, obstacle
values go up with yardage at the same course because approaches to greens
require longer clubs, and carries over hazards are more difficult. In any event, this methodology red flags Coto
de Caza for further examination.
Comparison with Men’s Obstacle Values
A course that is difficult for women
is usually difficult for men. Therefore,
the rank order of the Obstacle Values should be similar for men and women. This is not necessarily true. A course could be made relatively easy for women
by placing their tees in front of hazards that the men have to carry. Differences in rank order, however, should
pinpoint areas for more investigation.
Table 2 presents the ranking of courses by Obstacle Stroke Values for
both women and men.
The women's and men's rankings are
similar with two exceptions. SeaCliff is
ranked high in Obstacle Stroke Value for women, but is near the bottom for
men. This can be partly explained by
SeaCliff being a relatively short course for men and a course of medium length
for women. -- remember that Obstacle Values are usually higher the longer the
course. The other exception is El Niguel
which is ranked low in Obstacle Values for women, but high for men.
The Table cannot prove that the
ratings at SeaCliff and El Niguel are in error.
The comparisons in Table 2 can only raise questions. Why, for example, is the women’s Course Rating
relatively low at El Niguel when it is 200 yards longer than SeaCliff? Are the Obstacle Stroke Values at El Niguel
really that minimal?
Table 2
Ranking of Courses by
Obstacle Values
|
Scratch Obstacle
Value Ranking
|
Bogey Obstacle
Value Ranking
|
Course
|
Women
|
Men
|
Women
|
Men
|
SeaCliff
|
1
|
8
|
2
|
8
|
Coto de Caza
|
2
|
1
|
1
|
1
|
Mission Viejo
|
3
|
5
|
3
|
5
|
Santa Ana
|
4
|
7
|
6
|
7
|
Big Canyon
|
5
|
3
|
7
|
4
|
Mesa Verde
|
6
|
2
|
4
|
2
|
Old Ranch
|
8
|
9
|
5
|
9
|
Newport Beach
|
8
|
10
|
8
|
10
|
El Niguel
|
9
|
4
|
9
|
3
|
Dove Canyon
|
10
|
6
|
10
|
6
|
What Difference Do Errors Make?
Errors in estimating Obstacle Stroke
Values only have an effect when players from different clubs are
competing. Take for example, a player
from SeaCliff and Mesa Verde. Assume
that SeaCliff is overrated, and that it should have the same Scratch and Bogey
Obstacle Stroke Values as Mesa Verde.
Table 3 shows the change in index and home course handicap for a
SeaCliff Player under this assumption.
The
Table indicates the SeaCliff player would gain 1-stroke on her home handicap if
the Mesa Verde values were used. Since
her index also rises, she would also gain strokes depending on the Slope Rating
of the course when playing away. The
impact of a one-stroke swing on any individual player may not be great. The cumulative impact in competitions such as
team play, however, could be decisive.
Table 3
Differences in Index
and Home Course Handicap
Using Current
SeaCliff Obstacle Values
|
Using Mesa Verde
Obstacle Values
|
Index
|
Home Handicap
|
Index
|
Home Handicap
|
0.0
|
0
|
.9
|
1
|
5.0
|
5
|
5.8
|
6
|
10.0
|
11
|
10.7
|
12
|
15.0
|
16
|
15.7
|
17
|
20.0
|
22
|
20.6
|
23
|
25.0
|
27
|
25.5
|
28
|
30.0
|
33
|
30.4
|
34
|
There
is nothing to prove, however, that an error has been made. This paper is only intended to document a
methodology for highlighting possible errors, and stressing the impact on the
equity of competition that such errors can have.
APPENDIX
Course Rating Information
WOMEN'S RATING
|
|
Course
|
Yardage
|
Slope
Rating
|
Course Rating
|
Scratch
Obstacle Value
|
Bogey
Obstacle Value
|
|
Mesa Verde
|
5486
|
124
|
71.4
|
0.8
|
3.6
|
|
SeaCliff
|
5587
|
123
|
73.0
|
1.9
|
4.2
|
|
Big Canyon
|
5788
|
123
|
73.3
|
1.0
|
2.8
|
|
Old Ranch
|
5877
|
128
|
73.4
|
0.7
|
3.3
|
|
Mission Viejo
|
5698
|
126
|
73.2
|
1.4
|
4.1
|
|
Santa Ana
|
5866
|
125
|
73.7
|
1.0
|
3.0
|
|
Newport Beach
|
5790
|
122
|
73.0
|
0.7
|
2.2
|
|
Dove Canyon
|
5472
|
117
|
69.7
|
-0.8
|
0.8
|
|
El Niguel
|
5787
|
120
|
72.8
|
0.6
|
1.6
|
|
Coto De Caza
|
5369
|
132
|
71.6
|
1.7
|
6.7
|
|
|
|
|
|
|
|
MEN'S RATING
|
|
Course
|
Yardage
|
Slope
Rating
|
Course Rating
|
Scratch Obstacle
Value
|
Bogey Obstacle
Value
|
|
Mesa Verde
|
6285
|
129
|
70.7
|
1.2
|
4.7
|
|
SeaCliff
|
6060
|
115
|
68.7
|
0.3
|
1.5
|
|
Big Canyon
|
6362
|
123
|
70.9
|
1.0
|
3.2
|
|
Old Ranch
|
6201
|
114
|
69.4
|
0.3
|
1.1
|
|
Mission Viejo
|
6464
|
124
|
71.1
|
0.8
|
3.0
|
|
Santa Ana
|
6213
|
120
|
69.6
|
0.5
|
2.4
|
|
Newport Beach
|
6232
|
112
|
68.9
|
-0.3
|
0.0
|
|
Dove Canyon
|
6034
|
121
|
68.8
|
0.5
|
2.9
|
|
El Niguel
|
6483
|
125
|
71.2
|
0.8
|
3.2
|
|
Coto De Caza
|
6082
|
127
|
69.9
|
1.4
|
4.8
|
|
|
|
|
|
|
|
|
|
|
Obstacle Stroke Values can be calculated from the
formulas used in estimating the ratings for women:
Course Rating = Effective
Yardage/180 + 40.1 + Scratch Obstacle Stroke Value
Bogey Rating = Effective Yardage/120 + 51.3 + Bogey
Obstacle Stroke Value
Therefore,
SOV = CR -YARD/180 - 40.1
where,
SOV
= Scratch Obstacle Stroke Value
CR = Course Rating
YARD = Effective Playing Length
BOV = SLOPE/4.24 - CR + (YARD/120 +
51.3)
where,
BOV = Bogey Obstacle Stroke Value
SLOPE = Slope Rating