Law 6D2

[McBruce]

Law 6D2 allows for the possibility of a tournament based on deals from the past. Is it legal to insert just a few lesson hands into a game and have the rest shuffled or preduplicated? My plan is to insert a handful of lesson deals into one of the games that I run and give the players a sheet containing short write-ups of those hands only. (They want a short lesson and discussion session afterwards.) Even if the players don't get to the right contract or make the expected number of tricks, I still want to score the results obtained normally.

 

My initial plan is to put out two boards in each group when I arrive and then, from the third board in each set, make 3-4 lesson hands, and shuffle the other ones, so that players will not know which ones are the lesson hands, if that is a concern.

[jeremy69]

I would have thought that if this is a teaching session then you can do what you want but if you are passing it off as a regular game with, say, masterpoints for those who do well, then 6D2 prohibits what you are seeking to do.

[bluejak]

Duplicate with lesson hands is very common, surely. But I am afraid it is not legal. No matter, if that is what the customers want, just do it! :)

[pran]

I consider this legal if (and only if) the tournament has been specially announced to include such boards. A separate question is whether such tournaments are eligible for masterpoints etc., that is a matter of regulation.

[bluejak]

If it is against the Laws of bridge, it is not legal, whether announced or not.

[pran]

If it is against the Laws of bridge, it is not legal, whether announced or not.

Law 6D2 begins: Unless the purpose of the tournament is the replay of past deals no result may stand if the cards are dealt without shuffle from a sorted deck* or if the deal has been imported from a different session.

 

If the purpose is announced then it is obviously not against this law and thus fully legal. (There is no requirement that every deal in case shall be prepared, nor that the players shall know in advance which deals are prepared and which are not)

[bluejak]

"The replay of past deals" is nothing like "Hands constructed for any puropse". So it is not legal.

[pran]

"The replay of past deals" is nothing like "Hands constructed for any puropse".  So it is not legal.

(Unsuccessfully) splitting hairs, are you?

Law 6D2 includes hands dealt without a shuffle from a sorted deck. So hands constructed for a purpose are obviously included in the scope of this law.

[peachy]

"The replay of past deals" is nothing like "Hands constructed for any puropse".  So it is not legal.

(Unsuccessfully) splitting hairs, are you?

Law 6D2 includes hands dealt without a shuffle from a sorted deck. So hands constructed for a purpose are obviously included in the scope of this law.

Wait a minute! We can't put words or meaning in the law that is not there. You think the law "obviously" mean something not said in the law? I don't.

 

The Law says what it says and if an interpretation is needed beyond what the law clearly says, then some case law or some LC interpretation is necessary. Is there one regarding the OP issue? If there isn't, then outside of club games [when players like or want the lesson deals inserted] inserting them is illegal, announcement or not.

[jeremy69]

(Unsuccessfully) splitting hairs, are you?

 

I think the purpose of the law is to make things like setting up two or more copies of boards to ease sharing legal but not to have deals which are not randomly dealt either by hand or by machine in normal competition play. An exception in the 6D2 is made for the play of past deals in something like a simultaneous pairs. It seems pretty clear that for normal play having a set of boards where you have specifically fixed some or all is not permitted. I can well understand why this is a good thing for a lesson but not for normal play. I fail to understand why this is "unsucessfully splitting hairs" to say so unless perhaps the author wants to reach 1000 gratuitously unpleasant comments in 2010!

[McBruce]

The argument against this being legal seems to be that the inserted deals are not random; in other words, that deals constructed for the purpose of teaching a specific point have probably not originated with a random process.

 

That's fair comment, I suppose, and it seems that we all agree that even if it is against Laws or possibly ACBL regulations to do what I plan to do, it's an easily provided service that does very little harm and far more good. In fact, it's not like I dreamed up the idea myself; I remember a game I played in in my early days that did exactly this.

 

I do feel I have several responsibilities though:

 

--the deals should be spread throughout the range of boards so that nobody is likely to miss more than one

--the deals should not look "obviously constructed" as many do, with spot cards forming straight flushes regularly

--deals should be used that feature key decisions for all players, and when this cannot be obtained the key decisions should be equally distributed among compass positions.

 

The invitational club where I plan to do this is almost all non-Life Masters and they play eight three-board rounds almost every session, after which about half stay for lunch. The quality of play is painful to behold: recently I saw a player declare 5♣ with a trump suit of QJ8752 opposite a singleton ten. Low to the ten fetched the king from LHO...and the ace from RHO! I saw this happen and figured trumps were 5-1 and declarer had another loser. I was right, but it was RHO who had the long trumps! * ^_^

 

* and no conceivable reason to overtake...

[gordontd]

When I used to teach I would look out for deals in play that illustrated points I wished to make and then re-use them.

[pran]

"The replay of past deals" is nothing like "Hands constructed for any puropse".  So it is not legal.

(Unsuccessfully) splitting hairs, are you?

Law 6D2 includes hands dealt without a shuffle from a sorted deck. So hands constructed for a purpose are obviously included in the scope of this law.

Wait a minute! We can't put words or meaning in the law that is not there. You think the law "obviously" mean something not said in the law? I don't.

 

The Law says what it says and if an interpretation is needed beyond what the law clearly says, then some case law or some LC interpretation is necessary. Is there one regarding the OP issue? If there isn't, then outside of club games [when players like or want the lesson deals inserted] inserting them is illegal, announcement or not.

Please observe the footnote to Law 6: A ‘sorted deck’ is a pack of cards not randomized from its prior condition.

 

So any "constructed" deal has been "dealt" from a sorted deck.

For the purpose of Law 6 "sorted" does not imply sorted in any particular sequence, only that the deck has not been randomized.

[mjj29]

Please observe the footnote to Law 6: A ‘sorted deck’ is a pack of cards not randomized from its prior condition.

 

So any "constructed" deal has been "dealt" from a sorted deck.

For the purpose of Law 6 "sorted" does not imply sorted in any particular sequence, only that the deck has not been randomized.

I would have thought the correct law to quote for this was L6E4 (emphasis mine):

The director may require a different  method of dealing or pre-dealing to produce the same wholly random expectations as from A and B above

This being the law that allows you to do anything other than a hand shuffle and deal one card into each hand in turn. Specially constructed deals are not 'wholly random'.

[hrothgar]

I would have thought that if this is a teaching session then you can do what you want but if you are passing it off as a regular game with, say, masterpoints for those who do well, then 6D2 prohibits what you are seeking to do.

Agree completely with what Jeremy says...

 

If you are running this game as your own sponsoring organization, do whatever you please. Just make sure to announce this...

 

If, however, you are running a game under the auspices some regulatory body, and said regulatory body has any pretenses that it follows the Laws, then what you are doing is a big no-no...

 

I don't consider this any worse than ACBL gholashes, games where the director rigs things so that everyone gets a fair number of points, and any number of other perversions.

 

However, since you are asking, this is a violation of the Laws...

[Cascade]

I would think preselected hands would violate Law 6E4

 

"4. The Director may require a different method of dealing or pre-dealing to

produce the same wholly random expectations as from A and B above."

 

In that we could no longer guarantee random expectations e.g. its more likely than usual that a safety play would be required because it is more likely than usual that trumps break badly etc.

[barmar]

I was just thinking: it's well known that many players don't shuffle well enough, so the hands produced by shuffling and dealing aren't as random as those produced using a good computer random number generator. But 6D4 says that the alternate method of dealing must produce the same random expectations as hand shuffling. Doesn't that mean that we have to make the computer LESS random?

 

All those LOLs who gripe about "those damn computer-dealt hands" are right! :)

[Vampyr]

I was just thinking: it's well known that many players don't shuffle well enough, so the hands produced by shuffling and dealing aren't as random as those produced using a good computer random number generator.  But 6D4 says that the alternate method of dealing must produce the same random expectations as hand shuffling.  Doesn't that mean that we have to make the computer LESS random?

 

All those LOLs who gripe about "those damn computer-dealt hands" are right! :blink:

Under-shuffling does not make the deals less random. It can cause them to be flatter, particularly after rubber-bridge when the cards are collected into tricks that mainly consist of four cards of the same suit. However, the hands are still every bit as random as computer-dealt hands.

[Cascade]

I was just thinking: it's well known that many players don't shuffle well enough, so the hands produced by shuffling and dealing aren't as random as those produced using a good computer random number generator.  But 6D4 says that the alternate method of dealing must produce the same random expectations as hand shuffling.  Doesn't that mean that we have to make the computer LESS random?

 

All those LOLs who gripe about "those damn computer-dealt hands" are right! :blink:

Under-shuffling does not make the deals less random. It can cause them to be flatter, particularly after rubber-bridge when the cards are collected into tricks that mainly consist of four cards of the same suit. However, the hands are still every bit as random as computer-dealt hands.

I think flatter etc is less random. In the sense of less haphazard.

 

I would be very surprised if I was the only one to think this way.

[mjj29]

I was just thinking: it's well known that many players don't shuffle well enough, so the hands produced by shuffling and dealing aren't as random as those produced using a good computer random number generator.  But 6D4 says that the alternate method of dealing must produce the same random expectations as hand shuffling.  Doesn't that mean that we have to make the computer LESS random?

6E4 says that it must be as random as the procedure in 6A and 6B. 6A says "thoroughly shuffled", which the under-shufflers aren't doing, so it is they who are in breach of the law.

[bluejak]

I think flatter etc is less random.  In the sense of less haphazard.

 

I would be very surprised if I was the only one to think this way.

Well, I have to agree with Wayne occasionally! :D

 

Yes, I agree.

[helene_t]

Maybe it is a question of semantics, but IMHO if "less random" is to mean anything, then every distortion of the fair distribution (the one that makes every possible deal equally likely) is "less random". Formally, "randomness" could be defined as entropy, i.e. the sum of p*log(p), where p is the probability of particular deal.

 

So I agree with Wayne.

[mycroft]

As a cryptographer, I agree with <strike>Wayne</strike> Helene. Perfectly random is defined as p(deal X) = p(deal Y) for all X, Y; if some deals have a higher chance of being produced (the "flatter" ones), it's by definition less random.

 

In Bridge, it's actually an issue: if one knows that hands are skewed to the flatter end (more than, by sheer probability, they will be), it is sensible to build bidding systems around that fact, and to skew the card combination odds to reflect it. One will have fewer unbiddable or "least lie" hands that way; one will make more contracts that way. One will hate "those damned computer hands", though, because system, and play judgement, is now inferior to all the "true" systems that are inferior at the club. Please note, I strongly believe that 20 years ago, this actually was the case (without any intent; the "invisible hand" of the market, so to speak), at least outside the full-time tournament play set.

 

Interestingly enough, enough people in my area know about the "moar shuffels" thing that we tend to get the wilder hands, even when hand-dealt - the plural of anecdote is not data, but I've had two "ruff-sluff on the opening lead" hands in the last two weeks, and both were hand-dealt (I can't remember the one before them, of course). I've stopped griping about "those damned computer hands" (when we have a wild hand-dealt night) because the point has been made (I *used* to get "but they're not computer dealt...Oh.")

[pran]

As a cryptographer, I agree with <strike>Wayne</strike> Helene.  Perfectly random is defined as p(deal X) = p(deal Y) for all X, Y; if some deals have a higher chance of being produced (the "flatter" ones), it's by definition less random. 

 

In Bridge, it's actually an issue:  if one knows that hands are skewed to the flatter end (more than, by sheer probability, they will be), it is sensible to build bidding systems around that fact, and to skew the card combination odds to reflect it.  One will have fewer unbiddable or "least lie" hands that way; one will make more contracts that way.  One will hate "those damned computer hands", though, because system, and play judgement, is now inferior to all the "true" systems that are inferior at the club.  Please note, I strongly believe that 20 years ago, this actually was the case (without any intent; the "invisible hand" of the market, so to speak), at least outside the full-time tournament play set.

 

Interestingly enough, enough people in my area know about the "moar shuffels" thing that we tend to get the wilder hands, even when hand-dealt - the plural of anecdote is not data, but I've had two "ruff-sluff on the opening lead" hands in the last two weeks, and both were hand-dealt (I can't remember the one before them, of course).  I've stopped griping about "those damned computer hands" (when we have a wild hand-dealt night) because the point has been made (I *used* to get "but they're not computer dealt...Oh.")

This is not just theory.

 

Culbertson called attention to something he named "factor X" reflecting the fact that card shuffling was seldom perfect and as a consequence the theoreticdal statistics in bridge tended to be erratic.

 

The Italian Blue Team was said to "shuffle the spots off the cards" when they were being behind in a match at half-time.

 

The reason? They knew that better shuffling produced more distributional hands for which they werer at an advantage with their strong club systems.

 

Back to OP:

 

I understand some of the arguments on this thread that Law 6D2 permits replay of boards previously played, but not boards that have been constructed in any (other) way?

 

What a funny logic if (provided proper announcement and purpose for the event) it shall be legal to include deals exactly as they were previously played, but not such deals if they have been modified in order to better suit the purpose of the event. (Such purpose will often be training of novices in bridge)

[bluejak]

The point of this forum is to help people with the Laws, not to decide what they should be. If you think the WBFLC have got it wrong, kindly tell them - or at the very least take it to the 'Changing Laws & Regulations' forum.

 

When the Law book says "replay of past deals" it does not mean "constructed deals".