WHS - Slopes

Montgolfier wrote: »

Tramore is 113 but where that is on the scale I have no idea.

113 is the exact average. Harder than 113 and your handicap goes up, easier down.

To say that Slope measures course difficulty is slightly incorrect. It measures the difficulty for a 20 handicapper versus a scratch golfer.


For example if a course had a lot of hazards 180 to 200 yards off the tee then the it is assumed the high handicapper will find a lot of trouble off the tee but the hazards won't come in to play for the scratch golfer



- A slope rating of 113 means no adjustment to handicaps
- A rating lower than 113 means that it is relatively easier for the 20 handicapper so you would expect handicaps to be reduced.

- A rating higher than 113 means that is relatively tougher for the 20 handicapper and handicaps should be adjusted upwards for the round





Also courses should have different slope ratings for each tee.

mjsc1970 wrote: »

Have all courses had their slope rating done already? I've no idea of the slope rating of my own course.

Since when had Tramore or Portmarnock had their slope ratings calculated?

Pretty sure that all courses have had it done at this stage in advance of the changes.

May not be anywhere documented on your scorecard, etc...but I'm sure if you ask in the clubhouse they'll be able to tell you

HighLine wrote: »

Not at all. My course doesn't and apparently most Leinster courses have not have it done yet either.

I would imagine the new handicap system will be delayed coming in. They are giving November 2020 as the date for introduction... most places will be non-qualifying then anyway so maybe spring 2021.

They were looking for course raters early last year. Applications closed in March 2018 and they had five teams up and running at that time and were filling vacancies. It was specifically stated that they would be doing slope ratings. Hard to believe they've done nothing since then.

Ours was done last year. Around April iirc. Also know Tulfarris was done last year too.

Played Enniscrone during the week and on their card.
Blue tees 133
White tees 131
Yellow tees 123
Green tees 111.
You will find all the links have it done for years as they cater for the American market and they want to adjust their handicaps for the day.
It will be interesting I'm guessing I would be getting a shot or 2 playing Blue or White.

Seve OB wrote: »

The clubs may have done it themselves in the past but every club course will be rated now by the gui branches

Not sure clubs can actually do that. Even to get a SSS for a front nine or back nine requires a rating from the GUI. You can't just do it yourself, even if it's a straightforward exercise of taking the full 18 SSS. But I also checked the Enniscrone website and the slope rating was only added between July 2017 and April 2018. The PDF of the card doesn't have it and that's dated 2016. So it looks to me like the rating was done in or around the time that the GUI started rating courses for slope. Both courses there were done at the same time apparently.

martinkop wrote: »

Enniscrone have had a slope rating for years for the US market. Wasn't on cards but was in locker room, definitely back in 2011.

Thanks. That answers the DIY question. But the published ones seem to align pretty well with when the GUI started doing them.

prawnsambo wrote: »

113 is the base level multiplier for handicap calculation. The formula is:
((score - course rating) * 113) / slope rating = handicap differential.


So listing it at 113 means no handicap differential. In other words, they ether don't have a rating yet, or the site doesn't know it.

Just in terms of the above, is score = gross/net strokes?
And what is the course rating, is that the SSS/CSS?

So here's a rough calculation based on a Castlewarden member playing at Enniscrone. I'm setting the course rating at Castlewarden (Whites) to a hypothetical 75 (based on the slope of the white tees).

Your gross score is 92 off the white tees. That gives a handicap differential of ((92 - 75) * 113) / 117 = 16.41. So a handicap of 16.

Now we take that to Enniscrone and play off the white tees again. Your new handicap for that course is 16.41 * 131 / 113 = 19.03.

brick tamland wrote: »

I wonder what will turn out to be the Irish courses with the highest and lowest index’s? Enniscrone will be right up there you’d think. European club may take some beating. Struggling to pick out a lowest.

The links courses are all going to be up there, any course where u loose your ball if you miss the fairway it going to be rated hard.
The length of the rough when its rated I'm guessing will have a big effect on the rating.
When they are finished I reckon it won't take long for a magazine to issue a listing of the ratings.

So here are some I've collected so far:

Castlewarden (Blue/White/Yellow) = 119 / 117 / 114
Enniscrone (Blue/White/Yellow/Green) - 133 / 131 / 123 / 111
Kinsale (Blue/White) - 128 / 125
Dromoland Castle (Blue/White/Yellow) - 126 / 126 / 124
Beaufort (Blue/White/Yellow) - 137 / 133 / 129
Dooks (Blue/White/Yellow) - 122 / 121 / 117
Tulfarris (Blue/White/Green) - 129 / 125 / 122
Tipperary (Blue/White/Yellow) - 129 / 127 / 124
Mount Juliet (Blue/White) - 148 / 136
Old Head (Black/Blue/White/Yellow) - 142 / 139 / 136 / 129
Castlemartyr (Blue/White/Red) - 133 / 126 / 131

Some of these came from posters above, some from a quick Google search and some from scorecards from courses I've played lately.

I'm assuming likely landing area is on a pet day.
Where I play, our 9th us about 340 yards. Links course. Sutton. Pet day Drive, Sand Wedge. Last Saturday I couldn't reach it in two. I'm a 5 handicapper. Like Corballis on a nice day ye wouldn't know what all the fuss is about. On a more than average coastal windy day it can be soul destroying.

My point is, SSS used to work on course difficulty, length, etc and CSS used to look after all those variances of weather on any given day And your handicap was the same no matter where you teed it up. I don't know how WHS will work.

So in essence your handicap changes from course to course but the course ratings and slopes are constant.

OK this will be fun.

From what I can see, each hole is assessed independently and so have an individual rating for each tee although this would not be published. The individual holes would then be aggregated into an overall course rating which would be published. Individual hole ratigns would be interesting to see too. A course could have 9 very hard rated and 9 very easy rated averaging out to a 113 or could have 18 average rated averaging out to a 113.

Would there be seperate front-9 and back-9 ratings?

billy3sheets wrote: »

From what I can see, each hole is assessed independently and so have an individual rating for each tee although this would not be published. The individual holes would then be aggregated into an overall course rating which would be published. Individual hole ratigns would be interesting to see too. A course could have 9 very hard rated and 9 very easy rated averaging out to a 113 or could have 18 average rated averaging out to a 113.

Would there be seperate front-9 and back-9 ratings?

Probably yes. A bit like SSS, you can request a rating for individual nine hole layouts so that you can run qualifying competitions on them. Our course was SSS rated for the front nine as we hold nine hole competitions in the summer time on weekday evenings. Whether they would rate them like this automatically or on request, I don't know, but I suspect (given what you're saying above about individual hole ratings) that they would.

Snotty wrote: »

Seriously getting confused now.
So say I am a current 10 handicap member of Mount Juliet where the slope is (Blue/White) - 148 / 136
I'm not going to do the maths, but does that mean that after the change I'll be (as an example) a 11 of the whites and 12 off the blues?

Well first of all your handicap index (new name for handicap) will probably change anyway. This will be calculated on a rolling basis, but also as an average depending on the number of 'qualifying' rounds played. So 96% of average of best 3 from 9, best 5 from 15 and best 8 from 20 - called 'Equitable Gross Score. And then that is entered into the equation I gave before: (EGS - CR) * 113 / SR. That's your Handicap Index.

But when you're playing a different course (either another course or another set of tees), your Handicap Index is adjusted for that set of tees using the following forumula (I left the CR-Par bit out by mistake in a previous post): (HI * SR) / 113 + (CR - Par).

It sounds hellishly complicated, but the computer will do all that work for you and there will also be tables available to check what your HI would be on any given course/set of tees.

But to take your example, I'd need to know the course rating (CR) for both sets of tees. The CR is the scratch golfer's level of difficulty and is pure strokes like SSS. For the sake of simplicity, I'll use the SSS for those tees (73 / 72), Par is 72. The second thing to note is that if you're a member, your handicap index has already been calculated on a rolling basis. Assuming you've been playing off the whites and you're just moving to the greens (Mt. Juliet don't give a SR for the blue tees), then the calculation is: (10 * 136) / 113 + (72-72) = 12.03

Hope that helps.

billy3sheets wrote: »

From what I can see, each hole is assessed independently and so have an individual rating for each tee although this would not be published. The individual holes would then be aggregated into an overall course rating which would be published. Individual hole ratings would be interesting to see too.

And isn't there a potential conflict also with hole indices?
For example, Index 1 might not turn out to have the highest slope rating.

billy3sheets wrote: »

And isn't there a potential conflict also with hole indices?
For example, Index 1 might not turn out to have the highest slope rating.

To be fair, I'm not sure that hole indices are that accurate anyway. If you look back at scores over a year (assuming you've access to the data), you'll probably find that the hardest holes often aren't the lowest index ones. Our club published the previous year's data in the calendar and although index 1 played as index 1, index 2 was 3rd, index 3 was 2nd, index 4 was 5th etc. Only five holes played to their index. I'm sure if I looked back over a few years I'd probably find them different again.

Having said that, I'm pretty sure that the indexes are based on much the same criteria as the slope rating system; how the hole plays for the average bogey golfer. If you look at your high index holes and think about how it would play for someone who can drive the ball 200 yards max, and whether they would reasonably expect to get a GIR on it, you'd probably find that they align pretty well.