Course Rating

[louise_a]

I am a bit late to this thread but it is one I find interesting, when WHS came in my course had a course rating of 72.1 (par 72) and a course rating of 129, we then wanted a blue course rating and so they came and rerated all the tees, ours came in with a course rating of 70.8 and a slope of 122, off a handicap of 10 that makes a 1.7 difference in handicap.
Our course as several ditches, these are quite wide some as much as 30 yards wide, but apparently at such distances as to not affect course ratings.
All our handicaps have gone up, we had 3 three teams qualify from shield groups to county finals.
We really believe our ratings are too low.

 

[cliveb]

Why does how rough is assessed matter? Course rating appears to be so overwhelmingly based on length that all these other factors are of very minor importance.

 

[D-S]

Why does how rough is assessed matter? Course rating appears to be so overwhelmingly based on length that all these other factors are of very minor importance.

It can make quite a difference, see post 139

 

[mikejohnchapman]

Why does how rough is assessed matter? Course rating appears to be so overwhelmingly based on length that all these other factors are of very minor importance.

Not minor in all cases.

Before the courses are assessed the Course Manager is asked to provide details of green speed and rough length that the club would normally use in the playing season. These are checked on the day by the assessors and any significant differences discussed with the club. However, a lot of these measurements fit into ranges so the odd 6" on the stimp might not make any difference.

Your point re length is valid from the perspective of landing zones and distances to greens from previous shot. Not just the length itself but rather the situation at the point it lands / rolls. In simple terms there will be a higher factor assigned to a hole when hitting into a green with a 200 yard shot rather than a 100 yard shot. Mainly due to the protection / size of the green rather than whether you can hit a 4 iron or wedge correctly.

There is also judgement applied by the assessors. Criteria apply to all aspects but the assessors on the day make lots of judgement calls so it's not just a science.

Finally, things change. If you were assessed several years ago trees have grown, extreme rough may be thicker, fairways narrower (or wider). The assessment is based on what the team see and are told on the day - not what they believed from previous visits.

PS most clubs over-estimate their green speeds by a foot or more on the stimp!

 

[cliveb]

OK, so to all those who tell me that CR isn't overwhelmingly dictated by length.
I just checked the lengths and CRs of a number of courses in my general area. Here's a plot of them:



That looks very close to a linear correlation to me. Of course it's not a perfect straight line, but the variance is very small.

 

[VVega]

OK, so to all those who tell me that CR isn't overwhelmingly dictated by length.
I just checked the lengths and CRs of a number of courses in my general area. Here's a plot of them:

View attachment 54906

That looks very close to a linear correlation to me. Of course it's not a perfect straight line, but the variance is very small.

I assumed the conversation here is about the course rating in the more general sense, ie including both numbers: CR and Slope. Indeed, it’s only logical to see higher CR number for longer courses as it was before with SSS.

My understanding is though that the difficulty indication is the Slope number. Which is why Hotchkin is now billed as the most difficult in England (Slope 152).

 

[VVega]

Not minor in all cases.

Before the courses are assessed the Course Manager is asked to provide details of green speed and rough length that the club would normally use in the playing season. These are checked on the day by the assessors and any significant differences discussed with the club. However, a lot of these measurements fit into ranges so the odd 6" on the stimp might not make any difference.

Your point re length is valid from the perspective of landing zones and distances to greens from previous shot. Not just the length itself but rather the situation at the point it lands / rolls. In simple terms there will be a higher factor assigned to a hole when hitting into a green with a 200 yard shot rather than a 100 yard shot. Mainly due to the protection / size of the green rather than whether you can hit a 4 iron or wedge correctly.

There is also judgement applied by the assessors. Criteria apply to all aspects but the assessors on the day make lots of judgement calls so it's not just a science.

Finally, things change. If you were assessed several years ago trees have grown, extreme rough may be thicker, fairways narrower (or wider). The assessment is based on what the team see and are told on the day - not what they believed from previous visits.

PS most clubs over-estimate their green speeds by a foot or more on the stimp!

Thank you for details. Do the courses have a full report from the assessors or just the headline numbers? It’d be actually very helpful (in the spirit of transparency) to have these reports open to public, so everyone can see what makes the course easy/difficult etc.

Is there some grading of the rough in the course rating reference? E.g. one course can call 50mm as their “deep” rough, whereas another has 500mm - how would the raters process that?

The vast majority of non-championship courses can’t keep the same speed on all greens (or at least it’s an excuse for not posting their stimp).

I would guess that the majority believe they are running at 9, where in reality they are 8 or less?

 

[D-S]

Thank you for details. Do the courses have a full report from the assessors or just the headline numbers? It’d be actually very helpful (in the spirit of transparency) to have these reports open to public, so everyone can see what makes the course easy/difficult etc.

Is there some grading of the rough in the course rating reference? E.g. one course can call 50mm as their “deep” rough, whereas another has 500mm - how would the raters process that?

The vast majority of non-championship courses can’t keep the same speed on all greens (or at least it’s an excuse for not posting their stimp).

I would guess that the majority believe they are running at 9, where in reality they are 8 or less?

Re your first point see post 98.

Re your second point, yes there is grading, the course has to state rough height and this is verified during the visit. The same with green speed.

 

[nickjdavis]

My understanding is though that the difficulty indication is the Slope number. Which is why Hotchkin is now billed as the most difficult in England (Slope 152).

This understanding is wrong. Difficulty is defined by the course rating.

Slope merely indicates "relative difficulty" for a bogey golfer compared to a scratch golfer.

 

[IanMcC]

We got rated last summer and went down to a slope of 106..... The lowest in the region i imagine. We are also acknowledged as being pretty much the toughest course in the region. Ho hum.

You have my sympathies. I believe we spoke when I refereed at your course. Our course is also in Wales, and our director of golf is currently crapping himself, and our 10 yearly review is due next year, and will probably be done by the idiots that did your course. Its a terrible state of affairs that these ratings are not subject to review. So obviously a mistake at your course.

 

[wjemather]

OK, so to all those who tell me that CR isn't overwhelmingly dictated by length.
I just checked the lengths and CRs of a number of courses in my general area. Here's a plot of them:

View attachment 54906

That looks very close to a linear correlation to me. Of course it's not a perfect straight line, but the variance is very small.

At ~5800 yards you have courses with ratings that differ by about 3, with one of them rated similar to courses nearly 500 yards longer. Clearly, factors other than length are making a significant contribution.

However, in general, factors other than length have reasonably similar rating values from course to course, so length is naturally the overriding difference maker in their ratings.

 

[cliveb]

At ~5800 yards you have courses with ratings that differ by about 3, with one of them rated similar to courses nearly 500 yards longer. Clearly, factors other than length are making a significant contribution.

However, in general, factors other than length have reasonably similar rating values from course to course, so length is naturally the overriding difference maker in their ratings.

Yes, that's Yeovil. Clearly there will be outliers like this. The other one on this chart is Cricket St Thomas (5206, with a lower CR than the general trend). I've not played either of them so can't comment on why. But these outliers are rare.

Is length a more significant factor for scratch players than it is for bogey players (in the sense that you'd expect a scratch player far less likely to miss their target and end up in a hazard or the rough)? As a 15, I find the nature of the course away from the fairway has a much bigger impact than length.

 

[Swango1980]

Yes, that's Yeovil. Clearly there will be outliers like this. The other one on this chart is Cricket St Thomas (5206, with a lower CR than the general trend). I've not played either of them so can't comment on why. But these outliers are rare.

Is length a more significant factor for scratch players than it is for bogey players (in the sense that you'd expect a scratch player far less likely to miss their target and end up in a hazard or the rough)? As a 15, I find the nature of the course away from the fairway has a much bigger impact than length.

On better days of golf, factors away from the fairway are usually of much less concern.

 

[VVega]

This understanding is wrong. Difficulty is defined by the course rating.

Slope merely indicates "relative difficulty" for a bogey golfer compared to a scratch golfer.

Which is exactly why for the majority of golfers the difficulty of the course is indeed more indicative by the Slope number?

This is why (in my view) the WHS system is better in course rating. In the past, all we had scratch golfer or not is the SSS, now we effectively have SSS and Slope (for anyone but scratch golfers).

 

[VVega]

So I guess this could be done but it would be 144 A4 sheets of detailed information which I would guess would only be of interest to a tiny fraction of the membership.

But it would be much better than instead of guessing why the course seems to be rated differently to what they expect, if it was possible to simply refer to the report. Doesn’t cost much to scan a pdf and stick on the website.

Well, I suppose you could publish the form filled in by the club on green speeds and heights of cut and frequency of fairways, semi and rough which covers the whole course but members probably know/experience this anyway.

In my experience, this information is only divulged sporadically to the members, unfortunately, as the coms /gks prefer to have more flexibility on how the course is “presented”.

 

[D-S]

But it would be much better than instead of guessing why the course seems to be rated differently to what they expect, if it was possible to simply refer to the report. Doesn’t cost much to scan a pdf and stick on the website.


In my experience, this information is only divulged sporadically to the members, unfortunately, as the coms /gks prefer to have more flexibility on how the course is “presented”.

The information per hole would be extremely comprehensive but this is all fed into the WHS software and the result comes out, so unless your members compared all the details of all the holes with another course and do a lot of comparison calculations then they wouldn’t be able to understand the exact scratch and bogey differentials. I suppose it would indicate that a lot of effort goes into it but beyond that there would be little other point. I have been on the course rating team for many years and if you gave me all the sheets I wouldn’t have a clue as to what number would be derived from it.

 

[rulie]

OK, so to all those who tell me that CR isn't overwhelmingly dictated by length.
I just checked the lengths and CRs of a number of courses in my general area. Here's a plot of them:

View attachment 54906

That looks very close to a linear correlation to me. Of course it's not a perfect straight line, but the variance is very small.

I recall that someone else had done something similar (maybe a larger data set) and had also published the regression equation (a straight line equation).

 

[VVega]

The information per hole would be extremely comprehensive but this is all fed into the WHS software and the result comes out, so unless your members compared all the details of all the holes with another course and do a lot of comparison calculations then they wouldn’t be able to understand the exact scratch and bogey differentials. I suppose it would indicate that a lot of effort goes into it but beyond that there would be little other point. I have been on the course rating team for many years and if you gave me all the sheets I wouldn’t have a clue as to what number would be derived from it.

Appreciate what you are saying. Personally, I’d find it interesting to see the “breakdown” of each hole on its challenges merit. I bet most golfers don’t even realise what hazards come in play when/where. Could be great to see the course you play from the rater perspective.

 

[Arthur Wedge]

OK, so to all those who tell me that CR isn't overwhelmingly dictated by length.
I just checked the lengths and CRs of a number of courses in my general area. Here's a plot of them:

View attachment 54906

That looks very close to a linear correlation to me. Of course it's not a perfect straight line, but the variance is very small.

There is not doubt that the most significant factor for both course and slope rating is the length of the course

Local courses to us are rated “harder” because they are longer - the fact you can just smash it and not be in any trouble is irrelevant

 

[salfordlad]

OK, so to all those who tell me that CR isn't overwhelmingly dictated by length.
I just checked the lengths and CRs of a number of courses in my general area. Here's a plot of them:

View attachment 54906

That looks very close to a linear correlation to me. Of course it's not a perfect straight line, but the variance is very small.

That plot is commonly going to look like that because length is going to be closely related to par. A more valid read of difficulty of a specific course will come from how the course rating (not Slope) compares with the par. A long course rated at par or below is normally going to play more easily than a shorter course rated at 1 or more above par.