From: john@sequent.com (John Vander Borght)
Newsgroups: rec.sport.golf
Subject: Re: Slope???
Date: 9 Nov 92 22:17:02 GMT
Article-I.D.: sequent.1992Nov9.221702.5149
Organization: Sequent Computer Systems Inc.

Here is some information about ratings and slopes from the "USGA Handicap
System" handbook.


Section 17
USGA Course Rating: Definitions, Procedure

1. Definitions

  a.  YARDAGE RATING

  "Yardage Rating" is the evaluation of the playing difficulty based on
  yardage only.  It is the score a scratch player on his game is expected
  to make when playing a course of average difficulty.

  b. USGA COURSE RATING

  "Course Rating" is the evaluation of the playing difficulty of a course
  for scratch players.  Course Rating is expressed in strokes and decimal
  fractions of a stroke, and is based on yardage and other obstacles to the
  extent that they affect the scoring ability of a scratch player.

  Courses are ratehd by authorized golf associations, not by individual
  clubs.

  Note: Yardage Rating and Course Rating are not to be confused with par,
  which for handicapping, is too coarse a guage of playing difficulty; par
  for two courses differing 440 yards in length might be identical, but the
  Yardage Rating of the longer course would be two strokes  higher than the
  rating of the shorter course.

  c. USGA SLOPE RATING

  "Slope Rating" reflects the relative playing difficulty of a course for
  players with handicaps above scratch, whereas Course Rating is based
  solely on difficulty for the scratch player.  The lowest Slope Rating is
  55 and the highest is 155.  The average Slope Rating for men and women is
  113.

2. Yardage Rating Formulas

  Yardage ratings are obtained by using the following formulae:

  a.  YARDAGE RATING FOR MEN

	Yardage Rating = (Length of Course)/220 + 40.9

  If the Slope System is not used, deduct a Relative Length Factor of
  0.001 stroke for each yard the course is shorter than 6000 yards in
  length.

...

  b. YARDAGE RATING FOR WOMEN

	Yardage Rating = (Length of Course)/180 + 40.1

  If the Slope System is not used, deduct a Relative Length Factor of 0.001
  stroke for each yard the course is shorter than 5,500 yards in length.


3. Conditions for Rating

  a.  PLACEMENT OF TEE-MARKERS AND HOLES

  On the day a course is to be rated, the club should:

    (1)  Place tee-markers opposite the permanent yardage makers from
    which measurements were made.

    (2)  Cut the hole in each green at an average location commonly used
    during maximum play.  This should be a fairly easy location, probably
    near the center of teh green.

  There is a tendency to set the course to play long and hard.  This will
  result in a higher rating which will reduce handicaps for club members.

  b.  NORMAL PLAYING CONDITIONS

  Courses should be rated under conditions normal for seasons of maximum
  play.

  c.  RULES OF GOLF

  Course Rating shall be predicated on observance of the Rules of Golf.
  Any Local Rules must conform with the spirit of the Rules of Golf and
  USGA policy.


4. How to Rate Courses

  a.  PROCEDURE

  Course Rating is determined as follows:

  STEP 1 - Yardage Rating is determined by applying the total yardage of a
  course to the USGA Yardage Rating Formula.  Yardage must be measured
  accurately.  An error of only 22 yards in the overall length will change
  the rating by 0.1 stroke.

  STEP 2 - Course Rating is the Yardage Rating of a course modified by the
  factors described below.

  b.  MODIFICATION OF YARDAGE RATING

  Modification of the Yardage Rating is based on ten obstacle factors to
  the extent that they affect the scoring ability of the scratch player.

  On each hole, each factor is evalutated by the Rating Team on a scale of
  0 to 10.  When the rating process has been completed, units for each
  factor are totalled and multiplied by a relative weight factor.  The
  resulting figures are then totalled and applied toa  formula from which a
  number is produced.  This number, which may be positive or negative, is
  applied to the Yardage Rating to product the USGA Course Rating.

  c.  OBSTACLE FACTORS

  Following are the obstacle factors to be considered in determining the
  amount of adjustment to the Yardage Rating in arriving at the USGA Course
  Rating.

  (1) Topography
  Difficulty of stance in the landing area and the vertical angle of shot
  from the landing area to the green.

  (2) Fairway
  The effective width and depth of the landing area, which can be reduced
  by a dogleg, trees or fairway slope.

  (3) Recoverability and Rough
  The existence of rough and other penalizing factors in the proximity of
  the landing area and around the green.

  (4) Out of Bounds
  The existence of out of bounds in the proximity of the landing area and
  around the green.

  (5) Water Hazards
  The existence of water hazards in the proximity of the landing area and
  around the green.

  (6) Trees
  The startegic location, size, height and number of trees.

  (7) Bunkers
  The existence of bunkers in the proximity of the landing area and around
  the green.

  (8) Green Target
  The size, firmness, shape and slope of a green in relation to the normal
  length of the approach shot.

  (9) Green Surface
  The contour and normal speed of the putting surface.

  (10) Psychological
  The mental effect on play created by the proximity of the obstacles to a
  target area.

  d.  EFFECTIVE PLAYING LENGTH

  In addtion, the Rating Team must consider factors which cause a course to
  play significantly longer or shorter than its measured length.  These
  factors are:

  (1) Roll
  Unirrigated and thin fairways and downhill landing areas result in the
  ball rolling farther than the normal 25 yards.  Irrigated and lush
  fairways and uphill landing areas result in the ball rolling less than 25
  yards.

  (2) Elevation
  Holes which are uphill from tee to green play longer than those which are
  downhill from tee to green.

  (3) Dogleg
  Holes in which the fairway bends short of the normal drive zone will
  force the player to hit less than a full tee-shot.

  (4) Prevailing Wind
  Even though there may be as many holes with the wind as against, a
  constant wind, as on a seaside course, makes play more difficult.

  (5) Altitude Above Sea Level
  The ball will carry a greater distance in high altitudes.  The Yardage
  Rating of a course at an altitude of 2,000 feet or higher is adjusted
  downward to compensate.

  e.  BOGEY GOLFER; BOGEY RATING; SLOPE RATING

  A "bogey golfer" is one with a USGA Handicap Index of 17.5 to 22.4
  strokes for men and 22.4 to 26.4 for women.  A male bogey golfer can hit
  tee shots an average of 200 yards and can reach a 370-yard hole in two
  shots.  A female bogey golfer can hit tee shots of 150 yards and can
  reach a 280-yard hole in two shots.

  A "Bogey Rating" is determined by evaluating the obstacle factors from
  the standpoint of the bogey golfer.  It is equivalent to the average of
  the better-half of a bogey golfer's score under normal playing
  conditions.

  A "USGA Slope Rating" is determined by multiplying the difference between
  the Bogey Rating and the USGA Course Rating by 5.381 for men and 4.24 for
  women.  Under the Slope System, the average golfer receives more handicap
  strokes when playing a high slope course than he does when playing a low
  slope course.  The average USGA Slope Rating is 113.  A course receives
  such a rating when the difference between the Bogey Rating and the Course
  Rating is 21 strokes for men (21 multiplied by 5.381, a fixed value,
  equals 113) or 26.65 strokes for women.


Section 18
Installing Course Ratings in a Region

...
2. Personnel of Course Rating Team
  
  A Course Rating Team shall be composed of at least four individuals.  A
  Rating Team is to be assisted by a club representative, preferably a low
  handicap player ( or the club professional), who can inform the Team of
  any unusual conditions, including wind.  Team members should have, or
  have had, low handicaps and a practical knowledge of scratch players.
  The Team personnel should be fairly permanent, so that the ratings will
  be consistent.

  One member of the Team is to be designated as the Team Leader or Rating
  Captain.  The Team Leader must have attended a USGA Course Rating
  Seminar.  The Team is to evaluate each obstacle on each hole on a scale
  of 0 to 10 and should attempt to agree, within one unit, on an evaluation
  for each obstacle.  If such agreement is not reached, the opinion of the
  Team Leader should govern.  While rating a course, Team members may hit
  shots to assist them in evaluating obstacles.

  After the course has been rated, the Team should play the course to
  substantiate the rating results.  A rating form shall be submitted to the
  golf association for review.  A Rating Review Committe established by the
  golf association shall evaluate each rating.  This committee may modify
  the results within accepted limits, or it may direct a re-rating by
  another Rating Team.

...
-- 
"Practice random kindness and senseless acts of beauty!"
John Vander Borght
john@sequent.com