[tomkron]

I find I wish I could hide the barometer like I can hide My Results during matchpoint play, but on reflection I think it's because in showing the average of the played boards it gives the appearance that the early boards are more significant than the later boards. This makes an early bad board seem overwhelming or makes you watch as an early great board declines board after board (even after good boards).

Would it make sense to dampen the barometer so that early and later boards had more equivalent effect on what it showed? I'm thinking of something like populating a dozen (or however long the event is) boards all at 50% then as each board is played, replace that board with the actual percent. This would converge to the correct result at the end, but earlier boards wouldn't oscillate so wildly.

Thanks.

[steve2005]

No it's you.
Playing without barometer scoring face to face has the opposite effect happens if you can see the other results or your score with bridgemates.
1st board you always get 50% in the 1st round. This is completely meaningless.
That you got a good/bad score on 1st hand/round using barometer scoring isn't the end of the game.

[tomkron]

That bridgemate gives distorted barometer readings in face-to-face bridge is not really relevant to whether BBO's barometer could be improved in online bridge.

I know that an extreme result on an early board isn't the end of the game; indeed my objection to the current barometer is that it emphasizes the early results disproportionately making them seem artificially like they are the end of the game. That was my motivation for thinking to request an option to hide the barometer. Then I don't have to use post-its to hide it. But, on reflection, I thought the barometer could be modified to give each board equal apparent weight. This table shows the barometer readings I got on an actual average session, compared with what the hypothetical dampened barometer's readings would be after each board.

Board   Actual     Actual     Dampened
        Result    Barometer   Barometer
    
  1      7.1%       7.1%       46.4%
  2     50.0%      28.6%       46.4%
  3     53.6%      36.9%       46.7%
  4      7.1%      29.5%       43.2%
  5     14.3%      26.4%       40.2%
  6     85.7%      36.3%       43.2%
  7     67.9%      40.8%       44.6%
  8     89.3%      46.9%       47.9%
  9     57.1%      48.0%       48.5%
 10     71.4%      50.4%       50.3%
 11     82.1%      53.2%       53.0%
 12     57.1%      53.6%       53.6%

Maybe people would like it better, or maybe not; but I think I'd like it better.

[barmar]

I kind of like this idea as well. I play lots of robot duplicates and instant tourneys, and the extreme scores I see at the beginning are a marked contrast to how little the score changes when I get good or bad scores later on and the score just tweaks a little. The dampened barometer makes it clear that each board in a matchpoint game has equal weight. If you understand the math, you will realize that it's not really a problem, but it's hard to avoid an emotional reaction to all those really low barometer scores, and players might start trying to swing early on.

So seeing 46.4% after that disastrous first board makes it clearer that it's not an insurmountable problem. Had that board been last instead of first, it would have caused your score to drop from 57.8% (actual) or 57.1% (dampened) to 53.6%.

[tomkron]

Also, it mitigates the emotional impact of the barometer after a great first board, where your second board is pretty good but the barometer reading drops, then the third board is also pretty good but the barometer drops....

It's consistent with the 50% shown before the first board is played, too.

[barmar]

On the other hand, the logic of the current method is that it treats the boards you've played so far as if they're representative of how you play in general. So if you get 60% and 80% on the first two boards, it means "If you keep playing this well, you'll end up with a 70% final result."

There's not really any logic to averaging with 50% for the rest of the boards -- what does that have to do with your expected results?

[tomkron]

barmar, on 2017-September-12, 09:56, said:

There's not really any logic to averaging with 50% for the rest of the boards -- what does that have to do with your expected results?

There's some logic: 50% is in some sense the generic expectation for the typical player, so the dampening is making the assumption that future boards are more likely to regress to the mean than to continue being extreme. It might be interesting to look at a large dataset and see how effective early boards are at predicting session results, vs. using the prediction that non-average results will regress toward the mean.

That suggests, I suppose, that using a player's long-term average rather than 50% would be a better damper.

[barmar]

tomkron, on 2017-September-12, 11:31, said:

That suggests, I suppose, that using a player's long-term average rather than 50% would be a better damper.

Yeah, as soon as you said "expectation", I had the same thought. While 50% might be the expectation for a random player, the current player isn't random -- if he's a very good player, the expectation is probably closer to 60%, if he's a beginner it's around 40%.

But short of using the player's actual long-term average as the damper, that does suggest that 50% is better than the current running average. It's not uncommon to get 10% or 90% on the first board, but you rarely see scores outside th 30-70% range for a whole game, and most players' long term averages are probably in the 40-60% range. So 50% is not an unreasonable damper.

But on yet another hand, after 2-3 boards, perhaps your running average is more indicative of how you're playing that day.

All in all, I think there are enough pros and cons that it's probably not important enough to change.