[jallerton]

dburn, on 2011-March-13, 15:48, said:

Nor is Law 16B particularly relevant. But this is:

Quote

Law 16A
A player may use information in the auction or play if:
(a) it derives from the legal calls and plays of the current board (including illegal calls and plays that are accepted) and is unaffected by unauthorized information from another source.......

Now, in both the actual case and the example I have given, a player knows that his partner has no logical alternative to the action he has chosen. The player would not know this had he not misexplained his partner's call (in the actual case) or broken tempo (in my example). He cannot make use of this information, because it has occurred as a result of illegal communication and not solely as a result of legal calls and plays.

This is not so obvious to me in your hesitation example. It depends what the phrase "another source" in Law 16A is referring to. It could reasonably be interpreted that the first source is the player himself and so "another source" is any source other than the player himself.

[bluejak]

Why should another source be specifically what you say? I do not see any reason to interpret it that way.

[dburn]

jallerton, on 2011-March-14, 17:31, said:

This is not so obvious to me in your hesitation example. It depends what the phrase "another source" in Law 16A is referring to. It could reasonably be interpreted that the first source is the player himself and so "another source" is any source other than the player himself.

In the sentence:

"A player may use information in the auction or play if it derives from the legal calls and plays of the current board and is unaffected by unauthorized information from another source."

the only source actually mentioned is "the legal calls and plays of the current board", so "an[y ]other source" is "any source other than the legal calls and plays of the current board".

Of the aggregation of data that comprises "the auction together with all the original inflections", some items may be used by the side that contributed them while others may not. An example of the items that may not be used is: "call X was made in a manner that expressed uncertainty". Consequently, another kind of item that may not be used is: "call Y was made in response to call X despite the uncertainty with which call X was made", because that uncertainty may not be taken into account by either member of the contributing side (though of course it may by their opponents).

In the call "four slow diamonds", the words "four" and "diamonds" are legal while the word "slow" is not. "Slow" may not therefore be considered information from an authorised source, even by the player who made the call in the first place.

[AlexJonson]

While this has been so far a very interesting topic, it is certainly the case that it has 'drifted' a long way froom the origninal post.

[dburn]

AlexJonson, on 2011-March-14, 18:30, said:

While this has been so far a very interesting topic, it is certainly the case that it has 'drifted' a long way froom the origninal post.

Not very far at all, really. But perhaps it is time to address the additional data provided by aguahombre with respect to the original post. If agauahombre feels that this data was available or at any rate deducible from the original post, he may be right - but it does not matter very much.

aguahombre, on 2011-March-03, 17:54, said:

---

2♥ was explained by South as weak, sometime before the 2♠ balance.

North actually had an 11-count with 6 hearts (somehow deemed inappropriate to open one or two the first time).

Director asks for advice, and the person says that 3♥ is AI to South that North has a hand invitational to game, but that the 3♥ call is based on UI and should not have occurred ---since the authorized information is that South was rejecting a game invite and might not even have heart support.

If 2♥ was systemically weak but North had forgotten and thought it was invitational, then North was still (in effect) allowed to bid 3♥ if and only if he had a hand with which he would have bid an invitational 3♥ over 1♦ supposing that his methods permitted such a call. Perhaps he was asked what 3♥ over 1♦ would have meant, perhaps not; the information has considerable relevance, but is not supplied.

Well, North had an eleven count with six hearts - in other words, he really did have (or at least, may really have had) a hand worth an invitational 3♥ over 1♦. Maybe North didn't think of bidding that; maybe he did but decided that South might treat it as some sort of splinter or fit jump, and maybe he was right to be concerned.

In either case, North's 2♥-then 3♥ sequence was fine; it was the best he could do in the circumstances short of bidding a rather unilateral 4♥ (or a self-torturing 1♥ in the hope that it would not go "all pass"). I don't know what the North hand was, so I don't know whether I would do what the actual Director (or advisor) did, which was to cancel North's bid of 3♥. That could have been the right decision, but there is no certainty about it (and given aguahombre's description of the actual North hand, I would think it probable that the decision was in fact wrong).

What is certain is this: when South heard 3♥, it was not AI to him that North actually had a hand worth an invitational 3♥ over 1♦. South drew that inference (or "could have drawn that inference" - blackshoe is quite right that we should keep all our ducks in line) only because South knew that North knew that South had interpreted 2♥ as weak when North had not so intended it.

But South's knowledge of what North knew that South thought is not authorised (as I have tried to show). It did not derive solely from legal calls; rather, it derived from South's explanation of 2♥. Even though that explanation was systemically correct, it was not AI to North (aguahombre is quite right about that); and nor was the fact that North had heard it AI to South.

In short: even if North's bid of 3♥ was legal, South's bid of 4♥ was almost certainly illegal given his pass to 2♥.

[AlexJonson]

Thanks dburn. I think this brings things back to the OP.

For that matter, if you look back, it is more or less what I said. It is quite possible though not certain that North has no LA to bidding 3H (I partly borrowed that from hotshot). That's why I was interested in South's logic for coming back to life. Of course, it's also possible you might conclude that North and South both bid correctly, but South's explanation was incomplete and led to the 2S bid. Finally it's possible you might conclude N/S did everything correctly.

[Vampyr]

Coming late to this thread, I must say that I am very impressed by Mr Burn's explanation of "reverse UI". It seems to me a very important concept, and clearly correct, but little known. I think that the idea of "reverse UI" should be widely disseminated to players and included in TD training courses.

[nige1]

Vampyr, on 2011-March-19, 22:02, said:

Coming late to this thread, I must say that I am very impressed by Mr Burn's explanation of "reverse UI". It seems to me a very important concept, and clearly correct, but little known. I think that the idea of "reverse UI" should be widely disseminated to players and included in TD training courses.

I agree that reverse UI can exist but I can't see how it's relevant to this thread. The 2♥ response was explained as "weak". The 2♥ bidder had a six-card suit and eleven points. The 2♥ bidder was a passed hand so this was a misexplanation: in a passed-hand context this was not a weak-jump (minimum or maximum): It was strong. Furthermore, IMO, his partner's explanation that he had made a weak bid was unauthorised information to the 2♥ bidder.