Opp-strength-calibration in large pairs tourneys
#1
Posted 2016-November-15, 05:21
However, I don't believe our results were the 4th best. Of the 7 pairs we opposed, 6 scored below average and 2 were extremely poor scoring barely above 30%. Such anormalities are inevideble in very large tournaments without any prior info that can be used for seeding.
Now it could be that we were compensated for this by having more strong pairs playing in our direction. But there is no particular reason to think that was the case.
Obviously, we should somehow be compensated for the strength of the opponents and for the strength of our direction. This is not trivial since you don't want to fit the noise. Ideally, someone should let a Bayesian network chew the data.
This is a bit similar to the national ranking system of the EBU, but with microdata.
Anyone who knows if this is ever done?
#2
Posted 2016-November-15, 09:05
#3
Posted 2016-November-15, 09:16
Remember, you're mainly competing against the people sitting in your same direction. The people who got a big boost from this uneven distribution of strength were the few strong pairs sitting in the other direction.
#4
Posted 2016-November-15, 09:28
barmar, on 2016-November-15, 09:16, said:
it's not a partial Mitchell it's a scheveningen movement which is similar to 1/30 Howell in this case. so few other pairs will have had as easy opposition as we.
#5
Posted 2016-November-15, 09:33
Zelandakh, on 2016-November-15, 09:05, said:
well no since more than 7 opps would be impractical. 4boards per rround is an absolute minimum if you don't want too much of the day spent on reading convention cards. this is not ebu culture
#6
Posted 2016-November-15, 09:45
helene_t, on 2016-November-15, 09:33, said:
A pub bridge event is for fun, and anyway the prizes weren't vast sums, were they? You may be overthinking this. But it might have been nice for the event to be flighted, so that more people could get prizes.
#7
Posted 2016-November-15, 09:52
Vampyr, on 2016-November-15, 09:45, said:
Heh, they achieved this to give two bottles of wine to every pair whose rank was a multiple of five, lol This may sound silly but it is important to motivate a broad range of pairs to participate. So giving all the prices to the card sharks would not work.
#8
Posted 2016-November-15, 09:53
helene_t, on 2016-November-15, 09:28, said:
I'm not quite sure what you mean about the movement - is it a partial everlasting Howell? If so, I doubt you could do anything to ensure much in the way of balance. Otherwise, you could seed starting positions so that each group is roughly as strong as the others - we do this for EBU pairs events where entries are known in advance.
London UK
#9
Posted 2016-November-15, 10:22
gordontd, on 2016-November-15, 09:53, said:
I think the movement is probably as good as it can be given the practical constraints (only meeting 7/200 opps, not much useful info about strength). Sometimes they do segregate on the basis of self-described skill level (like: kitchen players, club players, 2nd/3rd class league players, 1st/main, higher). In this case they didn't segregate.
#10
Posted 2016-November-16, 09:55
Based on this data it is quite easy to make a number of groups (like now in champions league) from which you draw the playing list.
I do not know however how 'sophistacated' yr pub drive operates.
These drives have of course a large luck factor. Years ago our rather mediocre team won the Amsterdam pub drive, among other factors because in our last match the weakest player of our oppposing team chose to sit west instead of east and make a mess of all the easy decisions he had to make.
Greetings Maarten Baltussen