Plus Handicap Formula is Illogical

[Rincewindwiz]

On 11/7/2020 at 8:46 AM, Newby said:

No it isn't.  72 is 72. That is how 'hard' they both are.

But 140 indicates that it is relatively harder than 110 for a higher handicapper.

 

 

'Relatively Hard') seems a really good general description of slope.  But what about Course Rating? Its just the expected number of shots - which includes the two components of 'hard' namely length and difficulty (hazards etc)

 

So I go with Newby and think the best descriptions are

- course rating = how Hard a course is for the scratch golfer (SH)

- slope = how Relatively Hard a course is for the higher handicap golfer (RH)

and of course if you need it

bogey course rating = how Hard a course is for the bogey golfer (BH)

 

 

[Thayneil]

On 10/10/2020 at 2:33 AM, TrueBlue4Lyfe said:

no, no it’s not.  You guys want to play mental gymnastics and pretend “slope” isn’t a way of measuring difficulty but we all know that it is.  
 

No one in their right mind would argue a 72/125 is meant to be more difficult than a 72/145.

 

Rating and slope are supposed to work together to predict how a golfer will shoot.

slope measures how much more difficult  a course is for handicap golfers  relative to a scratch golfer

 

should have no effect on a plus guy

[Thayneil]

On 11/3/2020 at 1:15 AM, Rincewindwiz said:

Sorry if this has been said before but . . . .

 

Wouldn't it be much simpler and more logical if all slope adjustments ignored the sign (Plus or Not Plus) of the golfers handicap? After all big slope = harder course = higher handicap

 

So for example:

Ordinary mortal  CI = 12.2

playing on course with slope 130

Adds  a slope adjustment of 12.2*(130 - 113)/113 to their HI to get their CI which is 12.2+1.8 = 14.0

 

Ace Golfer CI = +4.0 (well -4.0 actually!)

playing on course with slope 130

Adds a slope adjustment of 4.0*(130-113)/113 = 0.6 to get their CI which is then -4.0 + 0.6 = -3.4

 

Or am I missing something?

thats  how it works

 

the slope  calc  should be reversed  or better still ignored for plus golfers

 

 

[DaveLeeNC]

49 minutes ago, Thayneil said:

slope measures how much more difficult  a course is for handicap golfers  relative to a scratch golfer

 

should have no effect on a plus guy

 

44 minutes ago, Thayneil said:

thats  how it works

 

the slope  calc  should be reversed  or better still ignored for plus golfers

 

 

Nothing like starting your day with a zombie thread. 

 

You could certainly make a case that the slope for play below the CR (possibly) should have a different slope. And you would make that case using data that the USGA already has. And you could implement it by adding another 'standard golfer' to the list of Scratch Golfer and Bogey Golfer (call him/her Plus10 Golfer). But to assert that the slope SHOULD BE exactly 113 (which is the effect of ignoring slope) would seem to require something more that just stating it should be so. 

 

If you want to reverse the application of slope (talk about illogical ...) then you have the case of the 4 handicap index golfer competing against the scratch golfer on a slope 140 course, and the 4 index golfer gets 5 strokes. They both work hard on their games and each improves his/her index by 4 strokes (so now they are a plus 4 and scratch respectively) and suddenly the weaker golfer only gets 3 strokes. 

 

There is no demonstrated problem to be solved here. But more analysis could be done to verify how well the current definition of slope applies to play below the CR. 

 

dave

Edited May 20, 2022 by DaveLeeNC

[Ty_Webb]

25 minutes ago, DaveLeeNC said:

 

 

Nothing like starting your day with a zombie thread. 

 

You could certainly make a case that the slope for play below the CR (possibly) should have a different slope. And you would make that case using data that the USGA already has. And you could implement it by adding another 'standard golfer' to the list of Scratch Golfer and Bogey Golfer (call him/her Plus10 Golfer). But to assert that the slope SHOULD BE exactly 113 (which is the effect of ignoring slope) would seem to require something more that just stating it should be so. 

 

If you want to reverse the application of slope (talk about illogical ...) then you have the case of the 4 handicap index golfer competing against the scratch golfer on a slope 140 course, and the 4 index golfer gets 5 strokes. They both work hard on their games and each improves his/her index by 4 strokes (so now they are a plus 4 and scratch respectively) and suddenly the weaker golfer only gets 3 strokes. 

 

There is no demonstrated problem to be solved here. But more analysis could be done to verify how well the current definition of slope applies to play below the CR. 

 

dave

 

Blast from the past here! Agreed by the way. What I say is if you're a scratch and you're playing a match against Scottie Scheffler, do you need more strokes on Southern Hills or on the local muni that's 6200 yards? Answer that question, then work through the math and see what you actually think should happen.

[nsxguy]

These kinds of discussions are always hysterical - well, at least some of the posts/opinions. 🙃

 

A "worldwide" agreement is (finally) reached on a fair way of making a match between 2 players of disparate skill and all "we" can come up with is "This ain't right because,,,,,,,,,".

 

Especially when said organizations realize the system can't be "perfect". But "we" always know better.

 

Maybe for golf we should round .4 to the next highest whole number ? You know, to make it more equitable.

 

Kinda sorta like me telling NASA that their liquid rocket fuel mixture should be an additional 10% oxygen. 🤦‍♀️

 

[sdemo]

On 5/20/2022 at 6:23 AM, Ty_Webb said:

 

Blast from the past here! Agreed by the way. What I say is if you're a scratch and you're playing a match against Scottie Scheffler, do you need more strokes on Southern Hills or on the local muni that's 6200 yards? Answer that question, then work through the math and see what you actually think should happen.

 

The USGA has said that the current system is (at least partially) based on the assumption that a scratch player should be a scratch player regardless of course difficulty (i.e. slope). In your example, I guess Scottie is the only variable, then, since he isn't scratch and the point of handicaps is to appropriately compare players.

 

Do you think Scottie should give a scratch player more strokes at Southern Hills than the local muni? If a scratch player always shoots scratch, and Southern Hills is much more difficult than a local muni, I would argue that - per the USGA's logic upon which the system is built - Scottie is getting the sh!t end of the stick by giving more strokes at more difficult courses. 

 

My point is this: the calculation is based upon a fallacy - that scratch players always play to scratch regardless of course difficulty, as measured by slope.

 

In practice, we know that a scratch player is going to be as affected (if not more so) by Southern Hills difficulty as Scottie. Do we also believe that the scratch player will close the gap to Scottie on the easy muni? Maybe. If so, perhaps the system is "functional," but it sure doesn't make "sense." 

[Ty_Webb]

3 minutes ago, sdemo said:

 

The USGA has said that the current system is (at least partially) based on the assumption that a scratch player should be a scratch player regardless of course difficulty (i.e. slope). In your example, I guess Scottie is the only variable, then, since he isn't scratch and the point of handicaps is to appropriately compare players.

 

Do you think Scottie should give a scratch player more strokes at Southern Hills than the local muni? If a scratch player always shoots scratch, and Southern Hills is much more difficult than a local muni, I would argue that - per the USGA's logic upon which the system is built - Scottie is getting the sh!t end of the stick by giving more strokes at more difficult courses. 

 

My point is this: the calculation is based upon a fallacy - that scratch players always play to scratch regardless of course difficulty, as measured by slope.

 

In practice, we know that a scratch player is going to be as affected (if not more so) by Southern Hills difficulty as Scottie. Do we also believe that the scratch player will close the gap to Scottie on the easy muni? Maybe. If so, perhaps the system is "functional," but it sure doesn't make "sense." 

 

Slope is not a measure of difficulty. It's a measure of *relative* difficulty. A course with a course rating of 72 and a slope of 125 is a harder course for a scratch player than one with a course rating of 70 and a slope of 135.

[Newby]

4 minutes ago, Ty_Webb said:

 

Slope is not a measure of difficulty. It's a measure of *relative* difficulty. A course with a course rating of 72 and a slope of 125 is a harder course for a scratch player than one with a course rating of 70 and a slope of 135.

Not quite. It's a measure of *relative* difficulty for a scratch player compared with a bogey (or non-scratch)  player

[Ty_Webb]

9 minutes ago, Newby said:

Not quite. It's a measure of *relative* difficulty for a scratch player compared with a bogey (or non-scratch)  player

 

Right - and a course that's relatively harder for a worse player is still relatively harder for a worse player if the worse player is below scratch. And the system makes perfect sense if you understand what it's doing.

[DaveLeeNC]

Just to further make the point that slope is not difficulty, assume that there is a dogleg hole with enough length and/or issues on the inside of the dogleg that a proto-typical (per the USGA) scratch golfer cannot carry the dogleg. 

 

Now make a change to the course such that the same scratch golfer now has a play across the dogleg, but the proto-typical bogey golfer has no chance even now. Clearly this course is now 'easier' than it was for golfers in aggregate. But the slope will go up (bogey rating mostly unchanged and the scratch rating will go down). 

 

dave

[Nels55]

1 hour ago, sdemo said:

 

The USGA has said that the current system is (at least partially) based on the assumption that a scratch player should be a scratch player regardless of course difficulty (i.e. slope). In your example, I guess Scottie is the only variable, then, since he isn't scratch and the point of handicaps is to appropriately compare players.

 

Do you think Scottie should give a scratch player more strokes at Southern Hills than the local muni? If a scratch player always shoots scratch, and Southern Hills is much more difficult than a local muni, I would argue that - per the USGA's logic upon which the system is built - Scottie is getting the sh!t end of the stick by giving more strokes at more difficult courses. 

 

My point is this: the calculation is based upon a fallacy - that scratch players always play to scratch regardless of course difficulty, as measured by slope.

 

In practice, we know that a scratch player is going to be as affected (if not more so) by Southern Hills difficulty as Scottie. Do we also believe that the scratch player will close the gap to Scottie on the easy muni? Maybe. If so, perhaps the system is "functional," but it sure doesn't make "sense." 

Scottie shoots under par on a tour course and at the local muni.  A scratch player shoots a little over par at the local muni and considerably worse at a tour course.  The course rating on a tour layout with tough pins is probably 75 or higher and that is the scratch guys target for par.  Also a scratch player averages over par as handicaps are based on the best 8 out of 20 scores.  A scratch player is going to need a lot more strokes to compete with a tour pro on a tour course then he will need at the local muni.

 

 

 

[sdemo]

58 minutes ago, Nels55 said:

Scottie shoots under par on a tour course and at the local muni.  A scratch player shoots a little over par at the local muni and considerably worse at a tour course.  The course rating on a tour layout with tough pins is probably 75 or higher and that is the scratch guys target for par.  Also a scratch player averages over par as handicaps are based on the best 8 out of 20 scores.  A scratch player is going to need a lot more strokes to compete with a tour pro on a tour course then he will need at the local muni.

 

 

I don't disagree with anything you've said (or anybody else who has since replied to my post, for that matter). However, rating isn't in question. The CH formula is essentially Y = MX + B (blast from the past, I know), where B = course rating - course par, so it is a constant adjustment for all players.

 

The part of the formula that is in question - and the reason for the thread in the first place - is the MX part. M (slope) = course slope / 113; and X = the player's index. 

 

The total potential change in CH due to slope change, 55 to 155, is -51% (55/113) to +37% (155/113), respectively. I'm not sure I agree that the variance should be that high, nor with the way that slope is determined. If slope is determined as relative difficulty between 0 handicap and bogey player (something most of us would just call "course difficulty"), then I think that slope is specific to the course and the players in question (strengths and weaknesses), and something so situational shouldn't be in the equation at all, or should have a less significant impact.

 

I closed my last post by saying that the formula is "functional" but doesn't make "sense" and I stand by that. 

Edited May 25, 2022 by sdemo

[DaveLeeNC]

1 hour ago, sdemo said:

 

I don't disagree with anything you've said (or anybody else who has since replied to my post, for that matter). However, rating isn't in question. The CH formula is essentially Y = MX + B (blast from the past, I know), where B = course rating - course par, so it is a constant adjustment for all players.

 

The part of the formula that is in question - and the reason for the thread in the first place - is the MX part. M (slope) = course slope / 113; and X = the player's index. 

 

The total potential change in CH due to slope change, 55 to 155, is -51% (55/113) to +37% (155/113), respectively. I'm not sure I agree that the variance should be that high, nor with the way that slope is determined. If slope is determined as relative difficulty between 0 handicap and bogey player (something most of us would just call "course difficulty"), then I think that slope is specific to the course and the players in question (strengths and weaknesses), and something so situational shouldn't be in the equation at all, or should have a less significant impact.

 

I closed my last post by saying that the formula is "functional" but doesn't make "sense" and I stand by that. 

 

I am not sure about the significance of this (and I have never looked for it, BTW) but I have never seen a course with a slope under about 90. Maybe they are out there, but I have never run into one that I remember. 

 

Situations vary and it would seem that a system that accommodates varying situations would be better than one that does not. 

 

A common use of the word functional would be something along the lines of 'gets the job done'. So if a system that gets the job done does not make sense to a someone, that would seem to me to indicate a lack understand a lack of understanding on the part of that person. 

 

You said that the difference between difficulty between a scratch and bogey golfer should be an absolute (rather than relative) measure of difficulty. It just isn't an absolute measure of anything - it is only relative. I can have 100x as much money as a friend, but I would have NO IDEA if I have a lot of money or not. I could be part of the elite 1% of this planet given some friends. And I would probably qualify for foodstamps and Medicaid given others. 

 

dave 

 

[Nels55]

2 hours ago, sdemo said:

 

I don't disagree with anything you've said (or anybody else who has since replied to my post, for that matter). However, rating isn't in question. The CH formula is essentially Y = MX + B (blast from the past, I know), where B = course rating - course par, so it is a constant adjustment for all players.

 

The part of the formula that is in question - and the reason for the thread in the first place - is the MX part. M (slope) = course slope / 113; and X = the player's index. 

 

The total potential change in CH due to slope change, 55 to 155, is -51% (55/113) to +37% (155/113), respectively. I'm not sure I agree that the variance should be that high, nor with the way that slope is determined. If slope is determined as relative difficulty between 0 handicap and bogey player (something most of us would just call "course difficulty"), then I think that slope is specific to the course and the players in question (strengths and weaknesses), and something so situational shouldn't be in the equation at all, or should have a less significant impact.

 

I closed my last post by saying that the formula is "functional" but doesn't make "sense" and I stand by that. 

I was addressing this statement:

4 hours ago, sdemo said:

Do you think Scottie should give a scratch player more strokes at Southern Hills than the local muni? If a scratch player always shoots scratch, and Southern Hills is much more difficult than a local muni, I would argue that - per the USGA's logic upon which the system is built - Scottie is getting the sh!t end of the stick by giving more strokes at more difficult courses. 

 

[Ty_Webb]

3 hours ago, DaveLeeNC said:

 

I am not sure about the significance of this (and I have never looked for it, BTW) but I have never seen a course with a slope under about 90.

 

 

The pitch and putt course in Flushing in Queens is I think something like 50/77. It's par 54, the greens are tiny and awful. I shot 58 on it and it wound up being my highest differential of the year. I thought I played alright considering and wound up with a 11.7 differential. To get to 11.7 on Bethpage Black off the blue tees you have to shoot 93

[nsxguy]

43 minutes ago, Ty_Webb said:

 

The pitch and putt course in Flushing in Queens is I think something like 50/77. It's par 54, the greens are tiny and awful. I shot 58 on it and it wound up being my highest differential of the year. I thought I played alright considering and wound up with a 11.7 differential. To get to 11.7 on Bethpage Black off the blue tees you have to shoot 93

 

That lil course is still there ? They even rated it ?

[Newby]

5 hours ago, Ty_Webb said:

 

The pitch and putt course in Flushing in Queens is I think something like 50/77. It's par 54, the greens are tiny and awful. I shot 58 on it and it wound up being my highest differential of the year. I thought I played alright considering and wound up with a 11.7 differential. To get to 11.7 on Bethpage Black off the blue tees you have to shoot 93

What is the length? I thought there was a lower limit for rating.

[Ty_Webb]

9 hours ago, Newby said:

What is the length? I thought there was a lower limit for rating.

18 holes I think it's about 1,050 yards. 

 

This was about 10 years ago. I think it's still there, but I'm not sure. 

[davep043]

9 hours ago, Newby said:

What is the length? I thought there was a lower limit for rating.

The course must be at least 3000 yards for 18 holes, or 1500 yards for 9 holes.  I'm not sure if that rule was in place 10 years ago.

[Ty_Webb]

19 hours ago, davep043 said:

The course must be at least 3000 yards for 18 holes, or 1500 yards for 9 holes.  I'm not sure if that rule was in place 10 years ago.

 

That would explain why I can't find the numbers online anymore.

[Golffan31415]

Old thread but I will try to give my thoughts to it, because I also just experienced this ‚flaw‘ in the system on my very own. 
My course here in Germany is rated 72.1/133 which means that when I shoot a 4 over 76, the ‚score differential’ (SG) is 3,3. (by the formula of 113/133 x (76-72,1)=3,3)

 

That basically means, that shooting a 4 over par on this course is actually a little better than 4 over par in general.

And this is the fact for all rounds played over par on this course. Because of the factor 113/133=0,85 all scores played over par will be made ‚smaller‘ than their actual number by around 15%.
 

This seems to be fine as the course is not easy.

 

Fortunately I was now able to play a -2 70. 
I thought: ,wow, that’s great. Shooting 2 under on a ‚difficult‘ (or at least not easy) course must be benefiting for my hcp a lot because it should be considered even better than -2.‘

Well, that does not seem to be the case. The earlier mentioned factor 113/133=0,85 lowers the value of my performance and it turns out to be a SD of around -1,8

(113/133 x (70-72,1)=-1,78

 

This does not make sense. Rounds over par will be considered 15% ‚better‘ than the actual score, because the course is tough (reasonable), but rounds under par are considered 15% worse than the actual score (nonsense).

 

All this being said, I want to come up with a solution for this kind of problem. And if I am not mistaken, this will also solve some of the other problems mentioned in this thread.

 

When calculating score differentials for rounds under par the formula should be adjusted as followed:

(1/(113/slope)) x (AGS-CR)=SD

 

For my example that would mean:

(1/(113/133)) x (70-72,1)=-2,47

 

In my world, a SD of -2,47 is more justified for a -2 70 round on a difficult course, than a SD of -1,78.

 

That would lead to a better estimation/valuation? (sorry, I am not a native speaker) of rounds that are played under par.

 

The new formula now also solves the problem for ‚easy‘ courses with a slope under 113 where before, the value of a subpar round was immensely high, although actually easier to achieve (i.e. (113/95) x (68-70,1) = -2,50  <-> (1/(113/95) x (68-70,1) = -1,77 )

 

You can make the math for the other examples mentioned in the thread on your own, but I am pretty sure it will also solve the problems for the ‚under par hcp golfers’ on varying courses and so on.

 

Please let me know what you think about my possible solution and weather you still see problems while calculating the HCP.

[Halebopp]

Two things, the Slope rating only represents the relative difficulty of the course to a bogey golfer in relation to a scratch golfer, it doesn't tell you anything about the absolute difficulty of the course. Secondly, a scratch golfer isn't the best possible golfer and therefore the Course Rating isn't the best possible score to which one could play the course.

 

The more obstacles you have on the course, the higher the Course Rating will be and, as those obstacles affect bogey golfers more, the Bogey Rating will be relatively even higher, causing the Slope Rating to go up.

 

Now, imagine a a completely flat golf course with no obstacles at all, just 18 teeing areas, flat fairway all around and 18 flat greens. The only deciding factor is how long and how accurate the players are. The Course and Slope ratings are going to be very low for such a course and it becomes very difficult for the scratch player to beat the Course Rating. If you have a course filled with bunkers and Penalty Areas (say par 72 with a 74.5/140 rating), it's realtively "easy" to beat the CR as long as you play well and keep clear of the obstacles. But when none exist (say par 72, 64.2/80), your only chance of beating the CR is being longer off the tee, more accurate with your approach shots and holing more putts as there's no advantage to be gained by staying out of trouble. Therefore it becomes more and more difficult to beat the CR. 

 

Another way of looking at is is the fact that the better a player is, the longer and more accurate he/she is.  And, the more precise you are with your shots, the less the obstacles affect your game. In other words, the course starts to resemble and play like that completely flat course with no obstacles at all. There are many more possibilities to beat the course rating on a course with lots of obstacles.

 

Edited September 15, 2022 by Halebopp

[Newby]

8 hours ago, Golffan31415 said:

Old thread but I will try to give my thoughts to it, because I also just experienced this ‚flaw‘ in the system on my very own. 

Please let me know what you think about my possible solution and weather you still see problems while calculating the HCP.

Remember, par has nothing to do with difficulty. 18 holes of 450 yards and 18 holes of 300 yards are both par 72.

[DaveLeeNC]

4 hours ago, Newby said:

Remember, par has nothing to do with difficulty. 18 holes of 450 yards and 18 holes of 300 yards are both par 72.

 

You can remove the word 'par' from the argument and replace it with the word "course rating" (CR) and the situation is the same. The fact that it is 'illogical (at first look)' does not mean that it is a problem, of course.

 

dave

[DaveLeeNC]

14 hours ago, Golffan31415 said:

You can make the math for the other examples mentioned in the thread on your own, but I am pretty sure it will also solve the problems for the ‚under par hcp golfers’ on varying courses and so on.

 

Please let me know what you think about my possible solution and weather you still see problems while calculating the HCP.

 

You are proposing to invert the 113/Slope factor for scores under the course rating (I just arbitrarily removed the word par). Right now if you shoot a score of 4 over the CR on a course of slope 113 and then shoot a score of exactly the CR, the differential difference between the 2 scores is 4. If you do this on a course with a slope of 141, then the differential difference is 3.2. Note that the improvement as quantified by differential is smaller on the higher slope course. I assume that you are OK with that as that is how it works now in the scoring range of scores above the CR. 

 

It works exactly the same way for scores below the CR. So if you did the same comparison on two scores of exactly the CR, and 4 strokes below the CR, the improvement (where lower differentials mean 'better') will be larger on the lower sloped course (just like before). 

 

If you think that something magical should happen to the relationship between scores and differentials once you get to the CR, an explanation of why it should be that way would be required. 

 

dave

Edited September 15, 2022 by DaveLeeNC