[calm01]

http://tinyurl.com/corl7t8

In this hand the bidding by GIB East really scrapes the barrel.

One of the joys of bridge is that it is about competing evaluations.

And my evaluation could be wrong in the long term but work on this hand or vice versa.

But sometimes a bid is so bad and so unlikely be the best bid, it lies clearly in the category of ugly. The double of 1!S by GIB East is fine but the self-rescue into hearts fits the ugly category. What is wrong with 2!C - it gives partner more choice at the 2 level and the opponents more chance of rescuing you. 1NT also gives the opponents an increased the chance of rescuing you by bidding on and you are no worse if they double you in INT as partner has another chance and a third chance when you redouble to find the best suit.

2!H is just a terrible choice - only 3!H or higher would be worse. Not even a palooka would make this mistake - more likely leaving the contract in 1S XX.

This is not a bug it is a complete failure of bridge logic which is likely to cost so much in one deal as probably ensuring the loss of a tournament.

Please fix this bug and any underlying basis for the logic (if any) that was used by GIB.

If it is a case of simulation error - just increase the number of hands simulated by a factor of 3 or more for lower versions of GIB. A small delay in GIB responding is a small price to pay for sensible bidding. And with servers so cheap, BBO can readily afford an extra server or two if required as this is so much cheaper than wasting programming effort tinkering with such a poor base product.

calm01

[barmar]

This isn't a simulation, the bidding rule says to bid the longest suit, and the highest ranked of equals, so it prefers majors.

There's no need to give partner a "choice on the 2 level" -- if he had a preference he would have bid it on the previous round.

And I checked what would have happened if East had bid 2♣ instead -- West would still have passed the double.

The fix I think we need to make is not with East's bidding but West's: It should only pass if all its other suits are equal length. Otherwise, it should always show a preference, and prefer a major over a minor.

[calm01]

Barmar,

Thankyou for the effort you obviously to put in before developing your reply.

The words "the bidding rule says to bid the longest suit, and the highest ranked of equals, so it prefers majors" is I feel sure a true reflection of GIBS code - I trust you. Just by merit of its truth does not make it anywhere approaching an optimal bidding rule in the situation GIB East finds itself.

The existing rule applied by GIB, as described by you, clearly makes poor bridge sense.

Please change it to based on something like "Partner, this is my longest 5+ suit or failing that my lowest ranking 4 carder. Feel free to bid another suit assuming I have at least 3 card support or perhaps just pass if happy or if not doubled or rescued by the opponents as we are in scramble mode here."

A rule and an underlying rationale such as this is much more likely to get us out of trouble/be rescued on the majority of occasions.

A better rule might be to bid 1NT requesting partner to choose the best landing spot (to include 1NT), and a optional redouble of 1NT for penalties with a good 19 if partner has chosen 1NT. But such a rule takes a level of bridge understanding between regular human partners it is unreasonable to expect from a computer program, even one partnering a copy of itself.

calm01

[barmar]

The reason to bid the highest suit first is so that if the opponents bid spades again you can compete in another suit without reversing. This won't come up with a minimum hand, but with a stronger hand East might want to compete some more. I assume you agree to bid like this when responding to a takeout double, which is where it's more likely to come up.

But really, East shouldn't be in this situation in the first place. Advancer is supposed to bid HIS preferred suit, and should only pass with no preference. The problem is West's Pass (he should bid 2♥), not East's choice of suit. The doubler doesn't usually have a 5-card suit, or he would have bid it instead of doubling.

Is your suggestion about bidding 1NT asking partner to pick a suit standard? I've never heard of it. We're not going to invent new conventions for GIB, we want this to be standard.

[gwnn]

barmar you are just flat out wrong on this one. it is normal to play pass as scrambling and it is absolutely normal to bid 4-card suits up the line by doubler, to try to look for a 4-4 fit on the 2-level. Competing is not important in this situation, finding a playable spot where we don't go for 1100 is.

[barmar]

OK, it shouldn't be hard to change this. It's not in code, it's in bidding rules.