Relativity of factors in assigning ratings and slopes - how does one know?

[Carl Johnson]

From another thread: "Your point about course ratings is a good one that I had not considered. More generally, I find that the ratings system is flawed because length is too dominant a factor."  https://www.golfclubatlas.com/forum/index.php/topic,73685.0.html

I have done ratings and slope work in the sense that I've been part of teams that go out on a course and take lots of measurements, make a few judgments, and enter the data, often in the form of a second code, in tiny little boxes on a paper "spreadsheet."  Someone then sends the spreadsheet to the relevant golf association authority, and then they stir the data into a pot and come up with ratings and slopes from various tees.

What I have never known is how the raw data I and others submit are translated to ratings and slopes.  I've been stonewalled at the association level.  But when I hear assertions like "length is too dominant a factor," I wonder how the speaker knows.  Several years ago I looked at the Pope of Slope website and didn't find what I was looking for.  And likely did other searches before giving up.  Is this sort of information publicly available, or is it under the USGA's and the associations' lock and key?

[Kyle Harris]

Length is literally THE factor in golf. Without having some distance between Point A and B you have... nothing.

[Erik J. Barzeski]

I've been the course rating captain in my area, have attended national seminars with the USGA on course rating, and am just about done with their (new) certification process.

Length is the dominant factor, but as Kyle says… it's that way for a reason. The farther a shot starts from the hole is the single biggest determinant of how close it finishes to the hole.

[Mark Mammel]

Much as I appreciate the work that has and does go into slope and course rating, it remains more art than science, at least in my experience. I say this because I play many rounds each year at 2 clubs, each in a  in different state, so each plays as a home course- I know the shots, no stress as when playing a new layout, etc.  One is rated at 69.0/127 for the 5823 yd tees I play, the other is is 68.0/122 at 5776 yds. Like clockwork, my index goes up 3 shots in about 4 weeks when I go from the first to the second, and goes back down 3 strokes when I return over the same time frame. I don't change, and this pattern has repeated over 10 years or so. So, I guess the first course is rated too hard, the second too easy, or a combination. My index over this period has been as low as 13 and as high as 17.5. I wonder if this is more likely a phenomenon that affects the higher handicap player, or are the single digit players seeing then same thing?

[Erik J. Barzeski]

Much as I appreciate the work that has and does go into slope and course rating, it remains more art than science, at least in my experience.

It's not really a science, but there's not much "art" to it. Almost everything is pretty objective, and the point of the national meetings and even the captain calibrations is to make sure the subjective has mostly everyone on the same page.

One course just may just suit you slightly more than the other.

[Tom_Doak]

Ratings and slopes are about handicaps, not about architecture.


They have a formula but that does nothing to account for the different goals of different projects.


I never worry about the course ratings or slope ratings for my courses.  I generally believe that my design philosophy will result in a relatively low slope compared to other highly regarded courses, but I don’t obsess on it, I’m thinking of how I imagine the holes will play for the full spectrum of golfers.


Good players often used to speak of courses that “separate the men from the boys” but I’m trying to bring them closer together, so that the better player still has to play well to win, instead of knowing that a weaker opponent will inevitably be beaten down by the course.

[Ally Mcintosh]

What we see in Ireland is that some of the raw, wild dune links courses on the west coast have lower ratings because they have less bunkers. It’s perhaps a flawed system that adds up 25 bunkers at one course and decides it’s easier than a flat parkland of the same length but with 85 bunkers….

[Sean_A]

What we see in Ireland is that some of the raw, wild dune links courses on the west coast have lower ratings because they have less bunkers. It’s perhaps a flawed system that adds up 25 bunkers at one course and decides it’s easier than a flat parkland of the same length but with 85 bunkers….

This happens a lot with links in general. The formula doesn’t quite work for links.

Ciao

[Ed Brzezowski]

What we see in Ireland is that some of the raw, wild dune links courses on the west coast have lower ratings because they have less bunkers. It’s perhaps a flawed system that adds up 25 bunkers at one course and decides it’s easier than a flat parkland of the same length but with 85 bunkers….




There may not be bunkers but those wild dunes point up also under " extreme". also the wind is a factor in seaside courses.

[Charlie Goerges]

I’m trying to bring them closer together, so that the better player still has to play well to win, instead of knowing that a weaker opponent will inevitably be beaten down by the course.

I like that. I'm fine with trying to give the weaker player a better chance. It's recreation after all (at least for most of us).

[Jeff M Johnson]

Erik,
In your training on the rating of courses, did you hear anything about using the hole by hole data gathered by the GHIN app to refine the rating process? It seems to me that this treasure trove of data could easily be mined to make the ratings of various courses more "even".  For example, what home course handicaps travel the best? The worst?  Etc. And adjust accordingly the course ratings and slopes.   

[Thomas Dai]

What we see in Ireland is that some of the raw, wild dune links courses on the west coast have lower ratings because they have less bunkers. It’s perhaps a flawed system that adds up 25 bunkers at one course and decides it’s easier than a flat parkland of the same length but with 85 bunkers….

I believe trees are also factored in. Something else that will likely result in lower ratings for tree-absent links courses.
atb

[Carl Nichols]

Erik,
In your training on the rating of courses, did you hear anything about using the hole by hole data gathered by the GHIN app to refine the rating process? It seems to me that this treasure trove of data could easily be mined to make the ratings of various courses more "even".  For example, what home course handicaps travel the best? The worst?  Etc. And adjust accordingly the course ratings and slopes.

This is a great question.  There's so much information out there that it seems like the data should be a big piece of the analysis.  To take a different example, each course has a rating from each set of tees--does anyone ever analyze all of the scores posted for just one course to see whether the different tee ratings make relative sense?  It seems like this would be especially doable at a private course, where the vast majority of rounds are played by the same pool of players across the various tees. 


In other words, if one set of tees at a particular course is rated 70.3/128 and another set is 72.5/133, do the score-posting data support those numbers?       

[Bob Harris]

I believe trees are also factored in. Something else that will likely result in lower ratings for tree-absent links courses.
atb



From the Manual:
In addition to the effective playing length, there are 10 obstacle factors evaluated on each hole for both the [/size]scratch player[/size] and the [/size]bogey player[/size].  These are: topography; fairway; green target; recoverability and rough; bunkers; crossing obstacles; lateral obstacles; trees; green surface and psychology.
[/size]
[/size]I can't speak for other Associations, but we do look at scoring history.  We are particularly interested in the number of PCC Adjustments (Playing Condition Calculation) a course may have.  If there are numerous PCCs in one direction, it would indicate that there may be a problem with the CR/Slope or in the daily course set up.

[JohnVDB]

Much as I appreciate the work that has and does go into slope and course rating, it remains more art than science, at least in my experience. I say this because I play many rounds each year at 2 clubs, each in a  in different state, so each plays as a home course- I know the shots, no stress as when playing a new layout, etc.  One is rated at 69.0/127 for the 5823 yd tees I play, the other is is 68.0/122 at 5776 yds. Like clockwork, my index goes up 3 shots in about 4 weeks when I go from the first to the second, and goes back down 3 strokes when I return over the same time frame. I don't change, and this pattern has rated over 10 years or so. So, I guess the first course is rated too hard, the second too easy, or a combination. My index over this period has been as low as 13 and as high as 17.5. I wonder if this is more likely a phenomenon that affects the higher handicap player, or are the single digit players seeing then same thing?

The Course Rating and Bogey Rating (from which Slope is derived) are based on the Effective Playing Length (yardage +/- things like roll, layup, elevation changes etc.) and the 10 factors mentioned by Bob. The result of all those may result in two dissimilar courses having similar ratings.
For example, one course may have lots of bunkers while the other has lots of trees.  One might have lots of water on the left of holes while the other has it on the right.  So, if you are right-handed player who slices and has trouble in trees, you might find the course with trees and water on the right harder than the one with sand and water on the left even though they may have similar ratings. I know raters who jokingly call water on the right "bogey water".

[Erik J. Barzeski]

In your training on the rating of courses, did you hear anything about using the hole by hole data gathered by the GHIN app to refine the rating process? It seems to me that this treasure trove of data could easily be mined to make the ratings of various courses more "even".  For example, what home course handicaps travel the best? The worst?  Etc. And adjust accordingly the course ratings and slopes.

Yes, and they do a lot of that analysis. There are flags raised with PCCs (too many, most often), and they can run reports on all these kinds of things.

In general, course raters do a pretty good job, so there often aren't many things to flag or correct.

[Carl Johnson]

I believe trees are also factored in. Something else that will likely result in lower ratings for tree-absent links courses.
atb



From the Manual:
In addition to the effective playing length, there are 10 obstacle factors evaluated on each hole for both the scratch player and the bogey player.  These are: topography; fairway; green target; recoverability and rough; bunkers; crossing obstacles; lateral obstacles; trees; green surface and psychology.

I can't speak for other Associations, but we do look at scoring history.  We are particularly interested in the number of PCC Adjustments (Playing Condition Calculation) a course may have.  If there are numerous PCCs in one direction, it would indicate that there may be a problem with the CR/Slope or in the daily course set up.

Thanks for all of the input.  It seems that the actual weight of the factors, and their interrelationship, if any, is a trade secret.  That's fair and I understand the reasons that would be true.  From my own limited experience the factor that I had the most trouble with, both in understanding how to apply it and whether it made sense, was the "trees" factor.

[Ed Brzezowski]

Ratings and slopes are about handicaps, not about architecture.


They have a formula but that does nothing to account for the different goals of different projects.


I never worry about the course ratings or slope ratings for my courses.  I generally believe that my design philosophy will result in a relatively low slope compared to other highly regarded courses, but I don’t obsess on it, I’m thinking of how I imagine the holes will play for the full spectrum of golfers.


Good players often used to speak of courses that “separate the men from the boys” but I’m trying to bring them closer together, so that the better player still has to play well to win, instead of knowing that a weaker opponent will inevitably be beaten down by the course.






Having just rated the back nine on Stonewall i see your point.   New tee going in on 18???

[cary lichtenstein]

When I was a rater, I used to have my own little system for rating golf courses, it was very subjective, and I'm sure it was rated from the eyes of a 4 handicap golfer and I'm also an artist. In other words, I certainly had a bias, so I think all raters have one whether they'll admit it or not.


Very difficult gets negative points for me, no fun is no fun.

[Tags:]

Tags: