It is clear that an obviously fair solution for the situation (boards played a different number of times) does not exist, but we must use something.

In the literature, there is an assumption that "all boards should count equally". This sounds a good principle, but the actual effect is highly dependent on how you do the counting and what equally means. Leaving that aside, I looked at why we use Neuberg.

The Neuberg paper by Max Bavin (https://www.ebu.co.uk/documents/laws-and-ethics/articles/neuberg-formula.pdf) takes as read that a top on a board with 11 results is better than a 65% result on a board with 101 results.

That is not at all self-evident to me.

What I am interested in is doing a simulation to establish how likely each case is. To do that I would need historical information as to how likely a given pair is to beat another given pair on any particular board.

Does anyone know if such a dataset exists? (clearly it will exist in the various P2P uploads to the EBU, but whether it is available and extractable is a different proposition).

Or maybe someone has already done such a simulation?

As usual, someone had taken the hand from the wrong board.

In fact, EW had taken the hands from board 35, and NS from board 36. Both boards were in the centre of the table with 35 on top.

All players were adamant they had done nothing wrong, and when I suggested that perhaps board 36 had been on top when NS took their cards, and then the order "corrected", I was again met with vehement denials. It's also possible board 35 was elsewhere when NS took their cards, but it's unlikely in a Swiss event.

So to the point of law.

Neither board can now be played - but who is "at fault"? With board 35 being on top, is that enough to determine that NS got it wrong, or is it AV/AV?

(They also complained bitterly about not being able to play the boards, as if somehow it wasn't their fault. Is it possible to award AV-/AV-?)

Anyone who really understands probability will know that "incredibly rare" events are not that rare at all, and it is not having one that is unusual.

I was called several times by players who were adamant they had played the hand before, and struggled to get some of them to accept that they hadn't.

https://www.bridgewebs.com/cgi-bin/bwor/bw.cgi?pid=display_rank&event=20260510_2&club=devon, boards 26 and 36.

I would be grateful if someone can advise urgently on this issue.

During play East, a defender, drops a card but catches it between his legs. No-one else could have seen the card, but East says "Ooops I dropped a Queen".

Clearly there is UI, but is the card a penalty card?

Would the situation be any different if it was possible for his partner to know which queen it was (e.g. because the other 3 were in Dummy)?

What if East thought it was a Queen, but actually it was a King?

There are arrowswitching guidelines, but how much comparison does there need to be to make it a 2 winner movement?

One board played in the wrong orientation doesn't seem enough, but what if a hesitation Mitchell with an arrow switch had the last round cancelled - is that still enough? Where does the boundary lie?

Incidentally I came across something I didn't know whilst investigating this. If a board has been played the wrong way round (NS hands played by EW) I have alway just corrected the pair numbers - indeed some scoring software has a special function to do this.

According to WB 8.87.1, you can't (shouldn't?) do this in a 2 winner movement.

Note it doesn't say you can't in the laws - but then the laws say nothing about 1- or 2- winner movements.

Does this mean the hand may not meet the definition of strong, or that it isn't guaranteeing a strong hand?

Look at this hand:

I would consider it suitable for an intermediate 2S opening, but it meets the strong criteria of "13 HCP in two suits containing 10+ cards".

Would it be allowed as an intermediate 2S opening?

For example it said that point ranges could be considered similar if one wasn't a subset of the other but the overlap was big enough as a proportion - for example a 15-17 range was close enough to a 16-18 range, but not to a 17-19 range.

There were other things about suit lengths too.

I now can't find this document. There is some (good) stuff in the commentary to the 2017 laws, but I don't think that's what I read.

Assuming I haven't dreamt this, does anyone know what document I'm referring to, and can they point me to it?

Thanks.

I've had a quick look in the Blue/White books and can't find anything to suggest that this is what should happen in this circumstance - could anyone point me in the right direction if that is correct?

This is something I've been working on for a while, and it's finally got to the point where I can share it.

DIDO stands for "Drop In, Drop Out", and is a method of running duplicate bridge events without...

1. Everybody being there at the Start
2. Everybody being there at the End
3. Any time pressure!

I find it invaluable both for non-serious holiday events, and for introducing learners to duplicate events (because of the lack of time pressure).

It is not intended to be a replacement for standard duplicate movements!

One of the interesting things about it is that it cuts waiting (non-playing) time in half.
 
For more information, see:
https://barndancecaller.net/dido.html

Some of you will, I'm sure, see no need for this. For anyone else, any feedback gratefully received.

Jeremy

I'm struggling to envisage a situation where 16C is relevant.

When the revoke is corrected, revoker's other card becomes a major penalty card, so knowledge of it is authorised to revoker's partner.

What am I missing?

(Of course we still have equity, but we don't need 16C for that.)

Some very interesting questions came up.

Law 40B2D states that "Unless the Regulating Authority provides otherwise a player is not entitled to any aids to
his memory, calculation or technique during the auction period and play". This statement is under a law entitled "Partnership Understandings", strongly implying that it refers to (and only to?) details of their partnership agreement. However, WB 1.64 implies a much wider remit.

I always understood that the only note you were allowed to make (and refer to) was what the contract was, and if it was doubled. Is this true? If so, is this from 40B2D / WB 1.64 or elsewhere? Where does the right to note and refer to the contract come from? 41C only gives a right to be informed.

Here comes the juicy bits:
1) The person enquiring, when declarer in a NT contract, always arranges his suits in hand so that any bid by an opponent are on that opponent's side of his (declarer's) hand. Is this allowed, or does it fall foul of the "no aide-memoire" rule?

2) When dummy, he does the same thing (declarer is aware of this). Is this allowed? This sounds to me like Dummy participating in the play.

3) Is declarer allowed to request that Dummy's suits be laid out in a particular order? If so, can this be used as an aide-memoire like with his own hand in 1 above.

From the same person:
4) Can you draw inferences from an opponent rearranging their hand? This suggests they have just played their last card in a suit (and are rearranging to red-black). By corollary with 74C5 it would seem wrong, but there does not seem to be a law prohibiting it/

1NT Announced by East as 15-17. West pipes up "Oh no it isn't". Fair enough, director called, and East advised of his responsibilities.

I'm not happy with the E's pass, and am minded to make them bid 4H (with 10 HCP opposite a 15-17 NT, if you're prepared to play in 3H then 4H is a clearly logical alternative choice).

But because of the ludicrous transfer bid, I can't poll on East's hand.

Do I have any alternative to making a judgement decision (in consultation with others)?

I can (and do) take a board off them, but that can be unfair to whoever they're playing.

I can of course award 60/40, but I need evidence that one side is at fault, and "it's always you" doesn't really count. If I instead award 50/50, their opponents will often (quite rightly) complain.

So I wondered if this would work as a condition of contest:

"Any pair consistently in the last 5% to finish a round will be deemed to be at fault if a board is taken away in any round through slow play, unless the Director determines otherwise."

Thoughts?

Result obtained by NS: 3Sx-2 500
All results for the board:
2S= 110
3H-1 -50
3Cx-1 200
3H-2 -100
2H-2 -100
2H-2 -100
2S-1 -50
4Hx-3 -500
3Sx-2 500
3Cx-2 500
3H-2 -100
3H-1 -50
3NT-1 -50
3Cx-2 500
4Hx-3 -500
2H= 110
3H-1 -50
3Cx-2 500
3H-4 -200
3H-2 -100
4H-2 -100

Do I adjust beyond the 3 Imps?

It's difficult because I can search by name but it doesn't tell me the EBU Number. How do I know which John Smith or Mary Davies is playing?

Is there any way of simply downloading an NGS list by EBU Number? (obviously excluding those who have set it to private)?

I'm aware it is possible to do something a bit helpful with EBUScore, but a) I can't work out how to, and b) I'm not always using EBUScore (e.g. online).

Law 74C4 suggests that it's a violation of procedure to draw attention to the number of tricks remaining to be made. However, the law book seems to make no comment whatsoever on how to handle this situation. Should we just call the director to bring the matter to their attention and hope they desist from this in future?

West deals and opens, let's say 1H.
North passes.
East responds, let's say 1S
South passes.
While West considers his next call North leads a card face up on the table.

On seeing an "opening lead", East began to spread her hand "as dummy".

My friend proceeds through Law 24 correctly, but, finally, I'm told: "The hand unquestionably belongs to E/W (game and possible slam) so North won't be tempted to continue the auction."

As a general rule though, can one use an undo in the play to adapt your play?

PS Undos arent allowed in the EBU BBO normally, but it was the last hand and a claim had been rejected so there was some confusion!

Declarer has DAQ, SQ
Dummy has CQ8, D9

Declarer claims saying "They're all winners".

They are not - there is a trump out.

If declarer pays SQ and throws CQ, she will lose two tricks, otherwise only one.

Given that declarer believes her hand to be high, is it illogical to throw CQ on SQ?

In both cases does a system card have to declare that 1NT may contain a singleton?

If no system card is provided, does that alter what is abbounced?

I was taught that this does not necessarily promise four spades, but partner can be justified as bidding as though it does. Does this still require an alert?

Defender leads S4, then quickly realises it's not his lead so withdraws it.

Declarer hasn't noticed, but Dummy has.

If dummy waits until the end of the hand (Laws 42B3, 43A1a,b), it's quite possible, even probable, that the action will be disputed.

What is Dummy's best option?