# BBO Discussion Forums: Calculation of Par - BBO Discussion Forums

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## Calculation of Par

### #1doubler

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Posted 2017-September-23, 17:45

All my friends and myself are becoming increasingly frustrated at the "par" calculations on BBO.

I am not sure of your method but in serious events, usually 1, 2 or 3 (depending on the number of times a board is played) of both the low scores and high scores are eliminated before par is calculated.

This method precludes the silly and extreme results from influencing par, although the participants in such results are still imp'ed against par, but that par is calculated fairly based upon the remaining results.

Currently, a player receives plus-imps for almost any plus score even perhaps for bidding 4S when 7S is cold.

Under ideal circumstances, one should receive a fair score even when holding poor cards - just like in a real team match or imp pairs.
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### #2steve2005

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Posted 2017-September-23, 17:58

"Currently, a player receives plus-imps for almost any plus score even perhaps for bidding 4S when 7S is cold."
Even with the new math no.

"Under ideal circumstances, one should receive a fair score even when holding poor cards - just like in a real team match or imp pairs. "
The calculation is a calculation is not fair or unfair. I don't recall ever getting an adjustment at imps when I held poor cards!?
Sarcasm is a state of mind
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### #3dokoko

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Posted 2017-September-24, 02:05

doubler, on 2017-September-23, 17:45, said:

All my friends and myself are becoming increasingly frustrated at the "par" calculations on BBO.

I am not sure of your method but in serious events, usually 1, 2 or 3 (depending on the number of times a board is played) of both the low scores and high scores are eliminated before par is calculated.

This method precludes the silly and extreme results from influencing par, although the participants in such results are still imp'ed against par, but that par is calculated fairly based upon the remaining results.

Currently, a player receives plus-imps for almost any plus score even perhaps for bidding 4S when 7S is cold.

Under ideal circumstances, one should receive a fair score even when holding poor cards - just like in a real team match or imp pairs.

lol

There are surely flaws in any calculating method, but you are as likely to profit from them than to suffer. If your opps bid and make a 20% slam without a fault of yours it's even more unfair but that's the game.

Concentrate on playing well and results will come. Or accept that you need a big portion of luck to win and complain when it's not there to make up for your faults.
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### #4barmar

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Posted 2017-September-24, 05:01

doubler, on 2017-September-23, 17:45, said:

All my friends and myself are becoming increasingly frustrated at the "par" calculations on BBO.

BBO doesn't score you against par. Did you mean "datum"? We don't calculate a datum, we simply calculate your IMPs against all the other pairs, then average them. Butler scoring with a datum was common when people scored bridge games by hand, because it reduced the number of calculations, but it's practically never used with computer scoring.

Quote

I am not sure of your method but in serious events, usually 1, 2 or 3 (depending on the number of times a board is played) of both the low scores and high scores are eliminated before par is calculated.

There are very few serious events that use IMP pairs scoring, so there's not much to compare with. ACBL only has one such event at NABCs, and the only major international event I can think of is the Cavendish Pairs. AFAIK, they don't use Butler scoring or throw out extreme results when calculating the IMPs.

### #5doubler

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Posted 2017-October-01, 15:45

Hi Barmar:
Thanks for your response. Perhaps I should have stopped at better stating the problem, rather than delving into the calculating methods to solve it. The problem is that their are many inexperienced players on BBO, which is great, but some of the scores are just plain silly. They are welcome to them, we were all there once, but their silly scores greatly affect the imp scores of more experienced players. This is why I suggested that a Butler-type scoring was more appropriate. Surely you cannot deny that it is a huge advantage to have good cards on BBO, because almost any plus scores well, whereas in real team games you can still do well with a negative score.

Maybe with your increasing membership, it is time to split the games into Novice thru-Advanced and Expert thru-higher. I know many players exaggerate their stated skill level but at least it might help. BTW, when selecting a name from the player-request-to-join table, checking the potential player's profile causes that window to pop up annoyingly over the first window. If several players request within a few seconds, the window popups are hard to handle. Thanks again.
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### #6smerriman

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Posted 2017-October-01, 16:16

I think doubler has a point - when solely talking about the main bridge club.

It's true that some silly scores can make it looks like you're scoring well, but in reality you're not getting scored better than the vast majority of other players - so in any tournament format when there's a final leaderboard, those silly scores are completely inconsequential.

In the main bridge club however, you're being scored against different players every hand, and thus if you happen to get a 'good' hand - or where someone else has a silly score - it'll look like you're doing well, and you won't get that final leaderboard to cancel things out.

Then again, you could always just play matchpoints.
Challenge event 14 is underway.

Feel free to send me a friend challenge of any format as often as you like. I'll always accept :)
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### #7CecoMaster

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Posted 2017-October-23, 02:06

For me best way to improve calculation is to increase comparison from 16 tables to 32 or 64 and cut off few % of best and bad results in calculation to have almost fair result for others...
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### #8barmar

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Posted 2017-October-23, 08:44

16 tables is already more than most club games and sections at f2f tournaments.

### #9CecoMaster

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Posted 2017-November-06, 10:59

barmar, on 2017-October-23, 08:44, said:

16 tables is already more than most club games and sections at f2f tournaments.

For main bridge club this is best solution.
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