[uva72uva72]

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IMPs, ACBL robot individual

In my opinion, this is another example of the ineffectiveness of the GIB implementation of negative doubles. If you consult the traveler for this board, you will find relatively few pairs playing in ♦ at a make-able level, and I believe that is because of North's decision to use a negative double.

The original premise of the negative double is to provide a bid for hands that can't otherwise be described with regard to their strength and/or distribution. Under that premise, a negative double is used only for hands that aren't strong enough for a free bid or don't have the distribution requirements for a free bid. So, for example, if RHO overcalls your partner's 1♣ opening bid with 1♠, double shows either a hand too weak for a free bid with 4 or more ♥ or a hand strong enough for a free bid with 4♥ but lacking the distribution for a free bid (usually interpreted to be a 5 card suit, not necessarily ♥).

In this instance, North has both the strength and the distribution for a free bid in competition, and should make it. Failure to do so results in North's subsequent bid of 3♦ showing "4+♥,4+♦,11+ total points" and forcing South to guess whether to pass 3♦ with a doubleton. On this hand, 11 Souths confronted this decision and 10 guessed wrong (although several were reprieved when North elected to bid again). If, however, North bids 2♦ immediately, it can subsequently rebid 3♦ to show its suit length and limit its hand, and South can pass in comfort.

As for the ♥ suit, South should strain to bid it if he/she has it and can do so later in the auction. I will point out, though, that GIB routinely bypasses the other 4-card major to bid 5-card minors in response to a take-out double of 1♥ or 1♠, so finding the major suit fit is apparently not of the same importance as finding the best strain to play in. This is what bidding 2♦ originally will accomplish much more often than using a negative double that misstates both strength and distribution.

[cloa513]

uva72uva72, on 2014-September-11, 19:07, said:

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IMPs, ACBL robot individual

In my opinion, this is another example of the ineffectiveness of the GIB implementation of negative doubles. If you consult the traveler for this board, you will find relatively few pairs playing in ♦ at a make-able level, and I believe that is because of North's decision to use a negative double.

The original premise of the negative double is to provide a bid for hands that can't otherwise be described with regard to their strength and/or distribution. Under that premise, a negative double is used only for hands that aren't strong enough for a free bid or don't have the distribution requirements for a free bid. So, for example, if RHO overcalls your partner's 1♣ opening bid with 1♠, double shows either a hand too weak for a free bid with 4 or more ♥ or a hand strong enough for a free bid with 4♥ but lacking the distribution for a free bid (usually interpreted to be a 5 card suit, not necessarily ♥).

In this instance, North has both the strength and the distribution for a free bid in competition, and should make it. Failure to do so results in North's subsequent bid of 3♦ showing "4+♥,4+♦,11+ total points" and forcing South to guess whether to pass 3♦ with a doubleton. On this hand, 11 Souths confronted this decision and 10 guessed wrong (although several were reprieved when North elected to bid again). If, however, North bids 2♦ immediately, it can subsequently rebid 3♦ to show its suit length and limit its hand, and South can pass in comfort.

As for the ♥ suit, South should strain to bid it if he/she has it and can do so later in the auction. I will point out, though, that GIB routinely bypasses the other 4-card major to bid 5-card minors in response to a take-out double of 1♥ or 1♠, so finding the major suit fit is apparently not of the same importance as finding the best strain to play in. This is what bidding 2♦ originally will accomplish much more often than using a negative double that misstates both strength and distribution.

Its more the dumb definition of 3♦ after a double- minimum 5 ♦ and limited to less than 13HCP- 9-12HCP or TP so South can easily pass. With 13+HCP or TP, he can bid 2♦.

[Stephen Tu]

uva72uva72, on 2014-September-11, 19:07, said:

My link

IMPs, ACBL robot individual

In my opinion, this is another example of the ineffectiveness of the GIB implementation of negative doubles. If you consult the traveler for this board, you will find relatively few pairs playing in ♦ at a make-able level, and I believe that is because of North's decision to use a negative double.

No, it's not the decision to use the negative double that's at fault here, it's the poorly defined followup bids with bad constraints. If North starts with 2♦, and plans to show hearts later, that's GF, will get too high with even more certainty. The hand's too good opposite a 4-4 heart fit to bury the hearts and not mention them IMO, if the opps raise spades there's too much danger partner has 4 cd hearts and you want to be in game opposite that. Neg double is totally normal if you are choosing not to GF the hand, which is reasonable.

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In this instance, North has both the strength and the distribution for a free bid in competition, and should make it. Failure to do so results in North's subsequent bid of 3♦ showing "4+♥,4+♦,11+ total points" and forcing South to guess whether to pass 3♦ with a doubleton.

Here is the problem, 3♦ should be limited to 4 only hearts, promise 5+ diamonds, and something like 11- total points, not 11+, then South can know to pass. The negative double should be constrained by failure to free bid. It's actually a good choice on this hand to neg double first, not poor, they just have to define 3♦ better.

Also 3♥ should maybe assumed to be 3♥ instead of 3+ ♥.

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I will point out, though, that GIB routinely bypasses the other 4-card major to bid 5-card minors in response to a take-out double of 1♥ or 1♠, so finding the major suit fit is apparently not of the same importance as finding the best strain to play in.

Well that's a totally different situation and also a bug that needs to be addressed IMO, it totally should be bidding unbid 4 cd majors ahead of longer minors in response to takeout doubles, generally.

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This is what bidding 2♦ originally will accomplish much more often than using a negative double that misstates both strength and distribution.

2♦ will bury the heart suit as noted. It's the meaning of 3♦ that needs to be fixed, not the decision to use the neg double. Unless you think the North hand is worth a GF, which is kind of aggressive missing AK of diamonds since bidding diamonds then hearts will often drive you to a no play 3nt.

[uva72uva72]

Doubling first and then bidding 3♦ is certainly workable if the 3♦ bid promises at least 5 good ♦. If you play 2/1 GF even after an overcall that is the only real alternative. But North will then have to make some other bid with the 4-4 11 count when 2♠ is passed back around.

I've raised the issue of giving priority to responding to take-out doubles with major suits vice minors but the idea doesn't seem to get any traction.

[Stephen Tu]

uva72uva72, on 2014-September-11, 21:11, said:

Doubling first and then bidding 3♦ is certainly workable if the 3♦ bid promises at least 5 good ♦.

With any normal agreements, 3♦ promises 5+ diamonds, usually 6 really. The only question is range, if *not* playing negative free bids, as GIB does, then it should be NF and limited, if playing negative free bids then this is forcing and unlimited (and in that case promising only 5).

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If you play 2/1 GF even after an overcall that is the only real alternative.

It has nothing to do with playing 2/1 GF after an overcall which few do. Bidding 2♦, by itself, doesn't create a GF. But bidding 2♦, then later bidding 3♥ does, it's a reverse and a new suit by responder, has to be GF in any normal sort of system. Thus your original suggestion of bidding 2♦ to stay lower doesn't make much sense, unless your plan is to bid 2♦ then 3♦ NF if the opponents compete. I'm suggesting the hand is too good opposite a heart fit, so you don't want to bury the hearts by declining to make a negative double and bidding 2♦ then 3♦. And double followed by 3♦ shows the hand almost exactly, although one could be slightly weaker for such action. It's a better sequence since you show both 4h and long diamonds, whereas bidding 2♦ and then 3♦ buries the hearts, and bidding 2♦ then 3♥ is somewhat of an overbid.

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But North will then have to make some other bid with the 4-4 11 count when 2♠ is passed back around.

Bidding 3♦ would be ridiculous on a 4-4 11 count; it's standard to double a second time with such a hand.

[uva72uva72]

I agree with you that bidding 3♦ on a 4-4 is ridiculous. Now we just need to get the software and system notes adjusted accordingly.

[iandayre]

Let's talk real bridge here. No call would have occurred to me other than the negative double. And no call other than Pass of 3D would have occurred to me as South. Now yes, I realize that playing with a GIB, 3H could easily be right. THAT is the problem here, but in my opinion your best chance of success is not trying to guess when GIB does not have its bid, but to act as if it did.

[uva72uva72]

Okay, but in this instance having its bid can mean that the robot has 4 ♦, or at least that's what the documentation says. I've gotten a lot of experience playing 4-2 fits when the documentation says the robot has 4+ cards in a suit, and given that 10 of 11 Souths also bid on, I'm guessing they have, too.

I'm clearly in the minority on the issue of negative doubles, and I won't raise the issue again. But the last time a real bridge partner made a negative double at the 1 level with a hand this strong and with this distribution, RHO jumped to 3♠, I bid 3NT and partner guessed to pass. The contract made exactly, but we were cold for a slam in partner's long minor (and got a near zero on the board).

But as I said, I won't raise the issue again.

[1eyedjack]

uva72uva72, on 2014-September-14, 23:58, said:

I'm clearly in the minority on the issue of negative doubles, and I won't raise the issue again.

I agree with you in principle that negative doubles are over-used, and a lot of players cannot see past the fact that they have 4 cards in the unbid major.

This hand may simply be a borderline case. Give him values to GF and there would be no question that bidding D is best.