Why would two players off the exact same HI and CH have different PH?

[LizAig]

As the title says we have two players high off 24 HI. They both have been given a CH of 24 but one has 95% PH of 23 and one of 22.

 

[D-S]

Are their exact HIs 24.0?

 

[LizAig]

Are their exact HIs 24.0?

Yes - I’ve checked on WHSplatform and both are 24.0

The bizarre thing is now I’ve looked other players also have the wrong 95%. I don’t see how rounding can be having an affect but could it be? I thought CH was a full number but is it a % behind the scenes?

25.2 CH 25 PH 23 - should be 24 (exact is 23.75)
14 CH 13 PH 13 - should be 12 (exact 12.35)
42.9 CH 43 PH 40 - should be 41 (exact 40.85)
13.9 CH 13 PH 13 - should be 12.3 (12.35 exact

 

[rulefan]

What is the exact CR, Par and Slope?

 

[LizAig]

What is the exact CR, Par and Slope?

CR 65.3
Par 66
Slope 114

 

[D-S]

Yes - I’ve checked on WHSplatform and both are 24.0

The bizarre thing is now I’ve looked other players also have the wrong 95%. I don’t see how rounding can be having an affect but could it be? I thought CH was a full number but is it a % behind the scenes?

25.2 CH 25 PH 23 - should be 24 (exact is 23.75)
14 CH 13 PH 13 - should be 12 (exact 12.35)
42.9 CH 43 PH 40 - should be 41 (exact 40.85)
13.9 CH 13 PH 13 - should be 12.3 (12.35 exact

If they are both 24.0 there is no way it is a rounding issue as the calculation is the same for both assuming they are both playing from the same tee sets on the same course. And are the same gender.

 

[LizAig]

If they are both 24.0 there is no way it is a rounding issue as the calculation is the same for both assuming they are both playing from the same tee sets on the same course. And are the same gender.

That’s my thinking too but I’m beginning to doubt myself _ especially as I emailed Club V1 to query it and they haven’t got back to me!

 

[louise_a]

Yes - I’ve checked on WHSplatform and both are 24.0

The bizarre thing is now I’ve looked other players also have the wrong 95%. I don’t see how rounding can be having an affect but could it be? I thought CH was a full number but is it a % behind the scenes?

25.2 CH 25 PH 23 - should be 24 (exact is 23.75)
14 CH 13 PH 13 - should be 12 (exact 12.35)
42.9 CH 43 PH 40 - should be 41 (exact 40.85)
13.9 CH 13 PH 13 - should be 12.3 (12.35 exact

CH is an exact number to several decimal places if there is another percentage to be taken off.

 

[rulefan]

That’s my thinking too but I’m beginning to doubt myself _ especially as I emailed Club V1 to query it and they haven’t got back to me!

Did they both use the same method to enter the competition and their scores? eg HDID PSI, simple cards or the EG app .

A thought. Was one a comp entry and the other general play?

 

[LizAig]

Did they both use the same method to enter the competition and their scores? eg HDID PSI, simple cards or the EG app .

A thought. Was one a comp entry and the other general play?

No - they are both playing in the same comp and knowing them I’m pretty sure both booked in using their phones. Scores aren’t entered yet as the comp is tomorrow.

 

[LizAig]

CH is an exact number to several decimal places if there is another percentage to be taken off.

So the 4 extra PHs (not the identical ones that started my question) are likely to be different because the CH is likely to be xx.xxx

 

[louise_a]

So the 4 extra PHs (not the identical ones that started my question) are likely to be different because the CH is likely to be xx.xxx

I have checked the examples you gave and the calculated playing handicaps were correct, so yes the CHs are xx.xxx which is the reason for the differences.

 

[Alan Clifford]

Yes - I’ve checked on WHSplatform and both are 24.0

The bizarre thing is now I’ve looked other players also have the wrong 95%. I don’t see how rounding can be having an affect but could it be? I thought CH was a full number but is it a % behind the scenes?

25.2 CH 25 PH 23 - should be 24 (exact is 23.75)
14 CH 13 PH 13 - should be 12 (exact 12.35)
42.9 CH 43 PH 40 - should be 41 (exact 40.85)
13.9 CH 13 PH 13 - should be 12.3 (12.35 exact

I can guess at this one. Although their handicap indexes are both 24.0, this is a statistic calculated by avereraging 8 numbers and then rounding to 1 decimal place. They may be doing the averaging on the fly. I came across an anomoly like this in South Africa and they told me that they hold differentials in their database to (if I remember correctly) to 6 decimal places. But even just averaging the eight 1 decimal point differentials and then multiplying the unrounded average by .95 and then rounding the results to integers could produce the anomally.

 

[Alan Clifford]

I can guess at this one. Although their handicap indexes are both 24.0, this is a statistic calculated by avereraging 8 numbers and then rounding to 1 decimal place. They may be doing the averaging on the fly. I came across an anomoly like this in South Africa and they told me that they hold differentials in their database to (if I remember correctly) to 6 decimal places. But even just averaging the eight 1 decimal point differentials and then multiplying the unrounded average by .95 and then rounding the results to integers could produce the anomally.

If you post both players' best 8 differential, we could do a machine precision calculation to check that bit of it at least.

 

[LizAig]

I can guess at this one. Although their handicap indexes are both 24.0, this is a statistic calculated by avereraging 8 numbers and then rounding to 1 decimal place. They may be doing the averaging on the fly. I came across an anomoly like this in South Africa and they told me that they hold differentials in their database to (if I remember correctly) to 6 decimal places. But even just averaging the eight 1 decimal point differentials and then multiplying the unrounded average by .95 and then rounding the results to integers could produce

If you post both players' best 8 differential, we could do a machine precision calculation to check that bit of it at least.

Steve’s 8 score differentials are 26.5, 20.5, 24.5, 26.5, 21.5, 26.5, 19.5 and 26.5

Cliff’s are 26.5, 21.5, 26.5, 19.5, 25.5, 20.5, 28.4 and 26.5

 

[Voyager EMH]

Steve 24.0 HI

Cliff 24.4 HI

Is this correct?
If so - should explain it all.

 

[D-S]

Steve 24.0 HI

Cliff 24.4 HI

Is this correct?
If so - should explain it all.

Oh, that's ruined the mystery of it all!

 

[LizAig]

Update!
After speaking to our regional handicap advisor and to Club V1 it turns out that Club V1 isn’t always computing the correct PH until the player signs in….so although the system recognised that a players HI has changed it isn’t updating the PH - when one player signed in it still said his PH was 23 but the label that came out said 22! Our regional advisors club doesn’t use Club V1 so she spoke to another EG rep who does use that system and they had exactly the same issue - 24 of their players, off the same HI, had different PHs.

The advice was to send an email to members letting them know their PH may not be correct on the online booking sheet but should be on the label (should!).

 

[Alan Clifford]

Update!
After speaking to our regional handicap advisor and to Club V1 it turns out that Club V1 isn’t always computing the correct PH until the player signs in….so although the system recognised that a players HI has changed it isn’t updating the PH - when one player signed in it still said his PH was 23 but the label that came out said 22! Our regional advisors club doesn’t use Club V1 so she spoke to another EG rep who does use that system and they had exactly the same issue - 24 of their players, off the same HI, had different PHs.

The advice was to send an email to members letting them know their PH may not be correct on the online booking sheet but should be on the label (should!).

 

[tobybarker]

this is why sign-in for all comps (or indeed any event) is a good idea....it forces ClubV1 to go and get the latest HCPs for a player. We had the situation where a visitor, who played last year's seniors open, came again this year but the system hadn't ever been prompted to update the guy's hcp....he'd changed index significantly in the meantime.

Just why it cant do that for you is beyond me.....but then, I was only a programmer for 20 years before finding a better profession