PCC review

[rulefan]

What is there not to understand?

Understanding the Playing Conditions Calculation (PCC)

Why is there rarely an adjustment for PCC on days when the playing conditions feel challenging?

• In order for the PCC to trigger an adjustment, a significant percentage of players must return scores which are higher or lower than their expected scoring range
• If significantly fewer players than anticipated submit a score within their expected scoring range, conditions are determined to be harder than normal
• If significantly more players than anticipated submit a score within their expected scoring range, conditions are determined to be easier than normal
• On days when the conditions are perceived to be difficult but there is no adjustment for PCC, this will be because a significant number of players have scored within their expected range
• Players are not expected to play to their handicap every time they go out, and this is reflected in the player’s expected scoring range that is used for the PCC
• Taking all of the above into account, there may be more days without a PCC adjustment than some would expect – even when the conditions feel challenging

 

[Deleted member 3432]

What is there not to understand?

Understanding the Playing Conditions Calculation (PCC)

Why is there rarely an adjustment for PCC on days when the playing conditions feel challenging?

• In order for the PCC to trigger an adjustment, a significant percentage of players must return scores which are higher or lower than their expected scoring range
• If significantly fewer players than anticipated submit a score within their expected scoring range, conditions are determined to be harder than normal
• If significantly more players than anticipated submit a score within their expected scoring range, conditions are determined to be easier than normal
• On days when the conditions are perceived to be difficult but there is no adjustment for PCC, this will be because a significant number of players have scored within their expected range
• Players are not expected to play to their handicap every time they go out, and this is reflected in the player’s expected scoring range that is used for the PCC
• Taking all of the above into account, there may be more days without a PCC adjustment than some would expect – even when the conditions feel challenging

What is a players expected scoring range?

Keeps getting referenced but yet to see it as a number.

 

[IanM]

 

[Imurg]

As I've said before, scoring can vary depending on how well people are playing when playing conditions are exactly the same from one day to the next.
Our playing conditions haven't changed significantly for weeks and yet PCC crops up from time to time because .....
Players play well one day and poorly the next....

 

[rulefan]

What is a players expected scoring range?

Keeps getting referenced but yet to see it as a number.

The algorithm is a trade secret apparently to prevent competing software houses copying it.

But my understanding is that the range depends on the standard of the individual player or their cohort (that is not clear but IMO more likely)). The higher the player's cap the greater the expected variance. Somewhere in the calculation there is a reference to standard deviation if that helps

 

[Foxholer]

As I've said before, scoring can vary depending on how well people are playing when playing conditions are exactly the same from one day to the next.
Our playing conditions haven't changed significantly for weeks and yet PCC crops up from time to time because .....
Players play well one day and poorly the next....

Remember that that has to be a 'trend' over the entire set, or at least a significant number, of scores.

 

[Backsticks]

What is a players expected scoring range?

Keeps getting referenced but yet to see it as a number.

A range isn't a number, it's a curve. And a different curve for each handicap.
At a guess, it checks how many scores are in the central 80%, or some statistically justified portion. And applies a PCC adjustment according to the number of scores higher or lower than the average normally in the 10% bands high or low of that.

 

[Swango1980]

Well, I appreciate some on this forum have questioned PCC. Others have rigidly defended it (basically a nothing to see here, it is based on thousands of scores, it must be right, certainly can't be questioned by any of you nobody's with only limited local knowledge). Not sure if I summarised that correctly

Anyway, just got the following information by England Golf:

Since the launch of the World Handicap System in November 2020, England Golf has received feedback from golfers, clubs and counties on a wide range of topics.

One of the most talked about aspects of WHS has been the Playing Conditions Calculation (PCC) and its lack of movement compared to the old Competition Scratch Score (CSS).

We have been analysing this very carefully across GB&I and have presented this to The R&A to help with their own research and that of other countries on this topic. As a result of this work, we can report that a change will be made to the algorithm that calculates PCC.

Statement from The R&A/USGA

Analysis of scoring data provided from 24 countries around the world indicates that a change to the rounding method used within the current PCC algorithm would increase the instance of an adjustment for abnormal conditions by an average of 5%.

For example, in countries where an adjustment for PCC only occurs on average 10% of the time on eligible days, this change will increase the average to about 15%.

This small change, recently approved by the Handicap Operations Committee, is in response to feedback from national associations that the current PCC algorithm is too conservative.
​

While this may feel like a small change, we expect the impact to be significant in highlighting days where a player’s performance was significantly different from that expected by the system.

Please note that there will be no change to the visibility of the calculation. This is an algorithm built within the WHS and is not available to clubs.

This change will not be made retrospectively and will take place on or around Monday 22 August.

At least the Handicap Authorities are more likely to act on feedback, and do further checks, than some individuals in here are seemingly willing to consider. Will be interesting if we notice any difference or not.

 

[wjemather]

Well, I appreciate some on this forum have questioned PCC. Others have rigidly defended it (basically a nothing to see here, it is based on thousands of scores, it must be right, certainly can't be questioned by any of you nobody's with only limited local knowledge). Not sure if I summarised that correctly

At least the Handicap Authorities are more likely to act on feedback, and do further checks, than some individuals in here are seemingly willing to consider. Will be interesting if we notice any difference or not.

No, you haven't. You are misrepresenting what others have said.

 

[Backsticks]

Interesting that they reinforce that they will not disclose the calculation. UHS was fully transparant. WHS is transparant in all detail - except PCC. Have they ever explained why. Or even if not, is it known why ? As long as they leave one part of the overall handicap calculation in a black box, people are going to question it.

 

[Swango1980]

No, you haven't. You are misrepresenting what others have said.

I thought certain people might say that

 

[IanM]

I thought certain people might say that

I thought it was a reasonable summary.... change your name name to "SwangoRules" and you will be allowed an opinion! Until then, go and stand quietly at the back!

 

[rulefan]

Well, I appreciate some on this forum have questioned PCC. Others have rigidly defended it (basically a nothing to see here, it is based on thousands of scores, it must be right, certainly can't be questioned by any of you nobody's with only limited local knowledge). Not sure if I summarised that correctly

Some have given an explanation of the principle to the best of the limited published knowledge and defended that principle but I can't remember seeing anyone who has said it can't be questioned.

Of course it must be remembered that the CSS process was introduced before the advent of widely available computer software. At many clubs it had to be done manually and therefore was fully available to all. It was a series of messy tables and I can't remember anyone querying the numbers in the tables.

 

[IanM]

Statement from The R&A/USGA

For example, in countries where an adjustment for PCC only occurs on average 10% of the time on eligible days, this change will increase the average to about 15%.

Please note that there will be no change to the visibility of the calculation. This is an algorithm built within the WHS and is not available to clubs.

This change will not be made retrospectively and will take place on or around Monday 22 August.

Putting my old Comms Hat on, and translating the above.

"Yeah, you were right, PCC is zero too often, so we are increasing the frequency of when it changes." "But we are not sharing the maths, or you'd be able to challenge what we've done."

"On or around" = vague date in case we screw it up

 

[IanM]

Some have given an explanation of the principle to the best of the limited published knowledge and defended that principle but I can't remember seeing anyone who has said it can't be questioned.

Of course it must be remembered that the CSS process was introduced before the advent of widely available computer software. At many clubs it had to be done manually and therefore was fully available to all. It was a series of messy tables and I can't remember anyone querying the numbers in the tables.

Neither can I. What I think was happening is that players had built up a "feeling" over time of when they expected a change in CSS and the perception was that "we" had a reasonable feel for it. This perception was (incorrectly) applied to PCC, and what players saw was quite different. Although the change suggests they were not as wrong as many argued in this thread!

 

[rulefan]

"But we are not sharing the maths, "

So Golfshake (et al) can't put a competing package on the market claiming it is exactly the same

 

[Jimaroid]

Yet more bad science on top of bad science.

I look forward to the next BandAid when this version of PCC still doesn’t behave the way they expect when used in the real world.

 

[IanM]

So Golfshake (et al) can't put a competing package on the market claiming it is exactly the same

That is also true..... good point. (Which I hadn't thought about)

 

[Junior]

Well, i have changed my mind about PCC....
I recently won a "major" board comp as my handicap went up due to 3 brutal competition rounds at a tough links course in 40mph winds.

For one of the rounds, no one broke par, I came 6th or 7th out of 100+ with 30 pts. In the old system I'm sure it would have been reductions only, but under WHS , despite a PCC of 3, a good score was knocked off and my handicap went up a shot, meaning at my home club, I got 2 extra shots. The other two rounds PCC didn't move.

This of course is tongue in cheek ..... PCC needed reviewing and I'm glad they have.

 

[RRidges]

Neither can I. What I think was happening is that players had built up a "feeling" over time of when they expected a change in CSS and the perception was that "we" had a reasonable feel for it. This perception was (incorrectly) applied to PCC, and what players saw was quite different. Although the change suggests they were not as wrong as many argued in this thread!

I can understand why the calculation is kept secret. But I of wish they'd explain the logic, if any, of why it's still so different to the previous (Congu) one.