Handicap Calculation

[jazman]

Could you please outline the calculations and procedures necessary for the development of a handicap?

Are there ever different rules applied?

Thanks very much.

[spidey]

Although many places will calculate this for you (unofficially as this is), here is the gist.

Your handicap is calculated from your last 20 scores posted.

First, you need to subtract the course rating from your score for each of your last 20 scores. eg. (rating: 67.7; your score: 85; therefore differential is 17.3). Do this for each of your last 20 scores.

Then, apply the slope of the course played to them. eg.(slope 120 on the course you scored 85. 17.3 * 113/120 = 16.23). Do this for each of your last 20 scores. (113 is an official constant meant to represent the slope rating of an average golf course)

Then take away the worst 10 out of the twenty. Average the remaining 10 and take 95% of the average. Drop the decimals after the first one and Presto.

Assume your index pops out as 14.7 and you want to play a match at a course with slope 129. Multiply your index 14.7 by 129/113 = 16.78. Drop the fraction, your handicap is 16 on this course.

spidey

[jazman]

I looked around on several sites and found tonnes of calulators but I wanted to know the fundamentals...

thanks again,

Regards

Jeremy Jazman Gordon

[Gary Hill]

Forgive me if I sound like I am beating a dead horse, but there stills seems to be confusion on a very important point.

Golf has one set of Rules to be followed. If you shoot 200, you shoot 200. The end.

However, if Tiger Woods shoots 200 "once" this year, some adjustment would have to made to reflect that this is not a normal occurrence. This adjustment is required so that players cannot "accidentally" shoot 200 before the club championship and "claim" a high handicap factor. This adjustment is done by Equitable Stroke Control. If you normally play at par, then 40 on a hole is ridiculous. For the purposes of calculating your handicap factor only, one over par is deemed to be a more realistic score and that score would be used when calculating your handicap factor. Nothing will change the fact that your scorecard says 40.

Equitable Stroke Control is just one of hundreds of requirements, stipulations, and adjustments needed for calculation of a handicap factor. The handicap system manual is close to 100 pages and I am no more able to outline the calculations and procedures required than I would be to "outline" the Rules of Golf.

The best I can do is: Add your total scores for each round played. Divide by the number of rounds played.
This will be your average score. Over time, this will remotely parallel your true handicap factor.

The purpose of trying to get our club recognized by the R.C.G.A. was to allow this highly complicated and technical process to be done for you. A handicap factor is, by design, not recognized when done by an individual.

A handicap manual may be obtained from the R.C.G.A.

BTW - Please do not even attempt to apply the "gist" of spidey's formula as it is totally incorrect.

[spidey]

Dan's old Handicap page

From: Former Senior Director of United States Golf Association Handicap Department Dean Knuth, as the developer of the USGA's Course Rating and Slope Rating System, became known in golf circles as: The "Pope of Slope".

Dean Knuth says....
Handicap differential: The first step in figuring your Handicap Index. You determine one for each round you play. Take your total score and subtract the Course Rating. Take the result, multiply it by 113 (the USGA's "average" Slope Rating) and divide it by the Slope Rating. Round the result to the nearest 10th.

Do the math: Bill shoots 92 from the white tees, which have a Course Rating of 69.9 and a Slope Rating of 121. His handicap differential for that round is 20.6 (92-69.9x113/121).

Handicap Index: Average the better half of your 20 most recent handicap differentials and multiply by 96 percent. Delete all digits after 10ths.

full text at: Handicap: Course rating and slope

RCGA FAQ

Handicap and Course Rating
Q. How is an RCGA Handicap Factor calculated?
A. 1. Determine Your Adjusted Score:
For handicapping purposes, Equitable Stroke Control (ESC) sets a maximum number that a player can post on any hole depending on your Course Handicap. Adjust your gross score downward using the following chart:

Player`s Handicap Limitation On Hole Score
0 or plus maximum 1 over par
1 through 18 maximum 2 over par
19 through 32 maximum 3 over par
33 and over maximum 4 over par


2. Calculate Your Differential: A handicap differential is the difference between the adjusted gross score and the Course Rating multiplied by 113 and then divided by the Slope Rating with the result being rounded to the nearest tenth. The following is an example for a course with a 71.5 course rating and a 130 Slope Rating:

Adjusted gross score 95
Course Rating 71.5
Difference 23.5
Handicap Differential 113 x 23.5 = 20.4
130

The value 113 in the above formula is the national standard for Slope ratings and is used to weight differentials.

3. Calculate Your Handicap Factor:

a. The Handicap Factor is computed from the best 10 differentials of the player’s last 20 rounds as follows:

Total of lowest differentials 147.1
Average 14.71
Average multiplied by 96% 14.12
Delete all numbers after tenths digit 14.1
RCGA Handicap Factor is 14.1

b. If fewer than 20 differentials are available:

Number of Acceptable Scores Differentials to be Used
5 or 6 Lowest 1
7 or 8 Lowest 2
9 or 10 Lowest 3
11 or 12 Lowest 4
13 or 14 Lowest 5
15 or 16 Lowest 6
17 Lowest 7
18 Lowest 8
19 Lowest 9


Your current RCGA Handicap Factor is recorded and certified on the reverse of your RCGA/Provincial Golf Association membership card (see below) by the designated official at your club. This is the only acceptable means of verifying your Factor for the purposes of entering a golf tournament.

geez Gary, I may not be perfect, but it was pretty close...
I did include a disclaimer that it was not official.

I for one don't subscribe to the belief that Handicap calculations are black magic that only the priests of the RCGA are permitted to fool with. I think we just want to see the nuts and bolts. We understand your advice that there are many stipulations and exceptions, just like with the rules.

RCGA authorized software suppliers for Handicap calculation

Order the RCGA manual here

spidey

Gary says...
BTW - Please do not even attempt to apply the "gist" of spidey's formula as it is totally incorrect.

ouch

[Gary Hill]

Let's go back to your original "gist" formula and apply my example to your formula with a course rating of 67.7 and a slope of 120.

A scratch player shoots even par on every hole except one par 4. On that hole he takes 32. He total score is 100. For the sake of convenience, let's say he does this twenty consecutive rounds.

According to your original "gist":

100 - 67.7 = 32.3
32.3 * 113/120 = 30.4 differential
30.4 * 10/10 = 30.4 average differential (last ten of twenty identical scorecards)
30.4 * 95% = 28.8
Handicap factor = 28.8

According to your update and applying Equitable Stroke Control:

32 would be adusted under ESC to 5
73 is the Adjusted Gross Score

73 - 67.7 = 5.3
5.3 * 113/120 = 5.0 differential
5.0 * 10/10 = 5.0 average diffential
5.0 * 96% = 4.7
Handicap factor = 4.8

Surely you don't consider 28.8 close to 4.8.

That was the purpose of my warning not to use the original "gist" formula and no "ouch factor" was intended.

BTW - There is only one set of Rules for golf. However, there are completely separate and copyrighted official handicap systems in use by the U.S.G.A and R.C.G.A. (including the calculation formula). Any references to the U.S.G.A. handicap system and use of the word "index" should be avoided in Canada.

[spidey]

OK Gary, perhaps I simplified somewhat by leaving out ESC and I remembered 95% instead of 96%, but it still seems to me to be essentially accurate.

I guess I'm thinking that I only need to use the ESC rule every few rounds, and even then it would only give me relief of a stroke or two for the entire round. The big reason for this rule is to prevent sandbagging (cheating), and I suppose it's my fault for assuming that jazman was an honest type.

Are you going to tell me that this answer was not a simplified one....

Gary posted...
The best I can do is: Add your total scores for each round played. Divide by the number of rounds played. This will be your average score. Over time, this will remotely parallel your true handicap factor.

I don't think you've addressed ESC here, and this advice would put a newbie just as far off base.

Anyway, I guess this horse is dead. Perhaps I'm just bewildered by your sweeping condemnation of my post when I expected just a correction to the errors for the benefit of the collective.

spidey

:

[Gary Hill]

I disagree that a handicap factor error of 24 points is essentially accurate.
I disagree that ESC needs to be used only every few rounds.
I disagree that ESC only gives relief of a stroke or two for the entire round.
I disagree that the big reason for ESC is to prevent sandbagging.
I disagree with your inference that correct application of ESC is an indication of a player's honesty.
I disagree that my calculation of average score would be interpreted as an official R.C.G.A. handicap factor.
I disagree that pointing out errors in your calculation is a "sweeping condemnation of my post".

[spidey]

Gary says...
I disagree that a handicap factor error of 24 points is essentially accurate.

I submit that you are purposely misinterpreting me. You are purposefully ignoring the fact that without an ESC issue, the calculation is accurate.

Gary says...
I disagree that ESC needs to be used only every few rounds.

I submit that you are purposely misinterpreting me. I never said it was to be selectively used. I said that it's only an issue every few rounds for ME. Most of the time, my scores are within the ESC guidelines and I rarely have to invoke the rule in posting MY scores.

Gary says...
I disagree that ESC only gives relief of a stroke or two for the entire round.

Now this is ridiculous. I specifically indicated that this example applied to ME. I can't believe you've been following me around and have ANY proof that my ESC adjustments have exceeded 2 strokes. It's impossible.

Gary says...
I disagree that the big reason for ESC is to prevent sandbagging.

Um, sandbagging is the use of a handicap that's higher than it should be. ESC is one tool that the RCGA uses to make sure that the handicap isn't higher than it should be. Perhaps there is more to sandbagging than ESC, but...????!!!!!!

Gary says...
I disagree with your inference that correct application of ESC is an indication of a player's honesty.

This is pretty vague. You sound like you're saying that a person who ignores ESC and posts his inflated scores is not dishonest!!!! Perhaps that's true, but I don't think that the committee would agree with you. Either way, it's against the rules. Gary, my friend, it sounds like you are arguing for the sake of arguing.

Gary says...
I disagree that my calculation of average score would be interpreted as an official R.C.G.A. handicap factor.

Gary says...
Over time, this will remotely parallel your true handicap factor.

I did not misquote you. I copied your words exactly. You have to take ownership of your own implications. I prefaced my original post with the fact that I was not giving the 'official RCGA handicap factor' as well.

Gary says...
I disagree that pointing out errors in your calculation is a "sweeping condemnation of my post".

Gary says...
BTW - Please do not even attempt to apply the "gist" of spidey's formula as it is totally incorrect.

This is a sweeping condemnation. This statement specifically says that no part of what I had posted was accurate. Gary? Perhaps you felt that what you said was different. The words say otherwise. Totally incorrect = sweeping condemnation. Give me a break.

Gary says...
The handicap system manual is close to 100 pages and I am no more able to outline the calculations and procedures required than I would be to "outline" the Rules of Golf.

and yet Gary says...
32 would be adusted under ESC to 5
73 is the Adjusted Gross Score

73 - 67.7 = 5.3
5.3 * 113/120 = 5.0 differential
5.0 * 10/10 = 5.0 average diffential
5.0 * 96% = 4.7
Handicap factor = 4.8

Interesting how you wouldn't pipe up with this information in the first place. Also interesting that you do not follow it up with saying that nobody should ever use this calculation because it is totally inaccurate and doesn't address the 'outline' of the 100 page RCGA Handicap guide.

I agree with you: you love to disagree.

spidey

[Kilroy]

Wow!

It is really easy to see both sides of this one. :

Spidey was trying to be helpfull and because of an ommiting mention of ESC was corrected.
"Although many places will calculate this for you (unofficially as this is), here is the gist."
As he said, this was just the "gist", not the full formula.

Gary takes the phrasing of these comments to the letter, because that is what a rules official must do.
It may seem like he is picking on you Spidey, but I really do not think so. He is being clear and consice, but because of his attention to detail, seems critical, even nit-picky. I can imagine that much of his job as a rules official is like that. Examine every factor of a situation and find the one that indicates a course of action decicively.

It may have been more helpfull on Gary's part to just offer up a reference to where we could find all the details (RCGA handicapping manual) and add in "dont forget to apply ESC"

The fact that Gary is a representative of OttawaGolf has no bearing on my comments.

Now kiss and make up you two.

[spidey]

I won't kiss him, but I've said my peace, I'm done.

I didn't start out with an agenda to be antagonistic. :o

I apologize for monopolizing bandwidth with my dissertations. :

I don't have anything against Gary. I think he's a great addition to the staff. I look forward to all his posts.

spidey


(My hidden agenda is actually to reach the 'driver' hall of fame. I'm a professional devil's advocate.) :

[Kilroy]

Well, you probably will get to be the first "Driver" the rate you are going.

Don't worry about the bandwidth. We got all we need.

"I'm a professional devil's advocate"
Ok, you are a big boy and can take care of yourself. I will mind my own business

New policy:
I will stay out of other people's flame wars
I will stay out of other people's flame wars
I will stay out of other people's flame wars
I will stay out of other people's flame wars
I will stay out of other people's flame wars
I will stay out of other people's flam....

Besides they are fun to read, I don't know why I worry about them so. The board would get boring without them.
By the way whatever happened to HÄnd|cÄp?