Club Management Focus: Winter 2019

Sim Pairs Scoring

When clubs hold heats of simultaneous pairs events, they publish results at the end of the evening, then the results are combined across the country and overall results are published on the internet. Pairs look at the overall results, looking at their score and the scores of other players at the club …

“Somebody's scores must be wrong!”

They cry, “we came top in the club with 56% and on your overall score we have only got 48%”. Worse still, “X & Y finished fourth at the club and they finished ahead of us and the pairs who were second and third.”

Players understand that because it is being re-scored across the field, and there are other results to be compared with, the overall results will be different from your own club results. But they do not realise how different – we have known differences as high as 20% in the past. When re-scoring the result overall, we don’t change anything, so as long as you send the right results in then the overall result will be correct.

The differences do puzzle players, and we get phone call, e-mails, letters. This is not an error in the scoring, but something that happens when you combine the scores from all the other clubs onto one result chart. Let me try to show you how it happens.

In a 6-table section the 'top' will be 10, with other scores of 8, 6, 4 and 2 with a bottom of zero. Overall, the top will be, say, 4000 with scores going down in steps of 2 to zero. A 'top' in the club will not generally score a top overall. It depends where that score fits in with the scores achieved in all the other clubs.

Consider the following board from a fictitious club heat. It is Board One from a 6 Table Mitchell (share and relay). On this board, due to the favourable position of several cards, 13 tricks are generally made in Clubs, but there is a reasonable defence to hold it to 12. 3NT should lose 5 tricks (but pair 7 E/W let it through!). 7NT doubled by Pair 4 North/South was a disaster.

Club traveller with local and overall match points

PairsContractScoreMatch PointsOverall Match Points
173NT =400.8213512649
292♣ +5190.645223478
3113♣ +3170.463283672
487NTX -6.140001053995
5103NT -1.50281363864
6125♣ +1420.10019602040

As you can see, in the Club, 5♣ +1 is top for North/South while overall it is worth less than 50% (scoring 1960mp, out of 4000) because the most common score overall was 6♣ (scoring 2742 MP) with many pairs making 13 tricks (for 3634mp). The East/West top with 1400 on the other hand was almost a top overall as very few North/South pairs tried 7NT (or they made more tricks).

You can see that the two pairs scoring a top in the club (6 N/S and 8 E/W) have vastly different overall scores. This one board will make 2% difference to their overall scores and this effect, were it to be replicated over a number of boards, causes the (sometimes gross) disparity between the club scores and the overall scores.

If players think their scores must be wrong, all they can do is to check to make sure that the scores and pair numbers have been entered accurately. Assuming that the results were entered correctly, the overall frequencies will show the overall scores for each result on each board, and this will show them if their good scores were really good, or their middling scores were actually really bad.