Bidding Question Analysis Program

[RossSCann]

What you are missing:

- the brains behind GIB stopped development 10+ years ago in favor of his "day job" running a company he started. This is main reason why it hasn't entered world championship since. Also GIB's inventor had some beef with the contest coordinator which is why it didn't enter last 2/3 years when he was still working on it.

- BBO "team of coders" is devoted to mainly programming BBO site itself, not GIB. And integrating the robots with the site itself for the tournaments/robot races etc., not working on GIB's skill. AFAIK they have like 1 guy, maybe 2 working on GIB, only really know enough to work on bidding database tweaking, not to make advances in defense/play.

 

I will try version of GIB from 2 years ago (bid patches only, play engine still from 2002) vs. wbridge I downloaded earlier this year, maybe 64 board match, see if it is still competitive or not (I have not really played wbridge extensively to form opinion). I assume wbridge comparable to Jack since they have been close matches in WC and swapping places from year to year. Don't know how long this will take, it is tedious doing it manually.

 

Maybe some contact can gin up a version of GIB that will run from a file N hands, per any file format GIB wants, and print results to a text file. This is really probably very simple to code if they have decent function architecture.

Or maybe they would realease source code.

[RossSCann]

It seems your program still has lots of issues. You still have a few hands that have 5-5 in the minors, which is impossible since North would rebid 2c, not 1nt. You have hands with North having 4 cd spades, which would have raised spades, not rebid 1nt. You have hands with 2245 and 1345 distribution that arguably would have opened 1c, not 1d, if the rebid planned was 1nt (if you open these hands 1d, it is with the intent to rebid 2c). You have hands with 16-17 hcp, which should not rebid 1nt (they should have opened 1nt, or rebid a new suit, possibly reversing). Your result matrix still has a handful of hands reaching 2nt/3nt contracts, which shouldn't be possible. You have something like 245 hands ending in 2H, which is too high given the distributional tally you posted. 2h should only be reached if North has 4 hearts, or 3 hearts and 1 spade. With equal length, or 2-3 in the majors, it's normal to give a preference. Following those rules with your deals, you'd only reach 2h 166 times. And that's before checking if your frequencies re HCP distribution and shape distribution are consistent with reality. After the 2h rebid, North should basically pass with 4 hearts or stiff spade, and bid 2s otherwise, which South would pass.

 

In any case, I don't think people other than yourself are going to really be interested in the output of your program. Why would we care how poor defense does vs. poor declarer play? I don't really have confidence that they would really cancel each other out, I'd rather just use double-dummy results. You say that "nobody is ever going to write code capable of expert play". I disagree with this. GIB *already* declares at an expert level IMO, at least after a few tricks when Gibson kicks in. Its problems are mainly in the bidding, and in the defense where its lack of signalling knowledge is a crippling handicap.

 

As for getting programs to get double-dummy/DeepFinesse results, there are already plenty of ways to do this. Thomas Andrew's Deal in Tcl, and Antony's port of this to python, already interface with Bo Haglund's double-dummy solver library, so you can write scripts to calculate results on a double-dummy basis. van Stavaren's dealer has code to interface with GIB's bridge.exe command line, which does have a double-dummy mode where it can read a hand from a file or stdin and output a result.

 

If you really wanted to program something that would be of use to people other than yourself, I would tackle the problem of feeding GIB a hand and a specified auction, and finding the *single dummy* result, then repeating for some large # of hands. This is theoretically possible using the console mode bridge.exe, but might be easier with access to the source code for the GUI. At one point there was a linux release of GIB including source code for the GUI, somebody may have a copy floating around somewhere. Or BBO could perhaps be convinced to re-release it. (I would also love it if they'd release mb.txt2 as Matt used to, the source of the bidding DB, would be useful for experiments). Maybe improving GIB's bidding DB could go open-source to some extent if BBO is willing, perhaps it would improve faster than what georgi can do on his own.

 

Yes, 16 cases out 500 have 5 Clubs. I wiil look at those. I don't care if anyone else uses my program, I am interested in competing with others interested in this development issue. The idea that bid decisions in the panels in the Bulletin are scored by "informed judgement" strikes me as nonsense, for want of a better means. But then I was trained as a scientist. I will try to get source code for GIB to be used only for non-comercial purposes.

[aguahombre]

The idea that bid decisions in the panels in the Bulletin are scored by "informed judgement" strikes me as nonsense, for want of a better means. But then I was trained as a scientist.

The alternative being what? Bid decisions being scored by uninformed machines programmed by a scientist who then decides which perameters are the appropriate ones for each particular case based on his own style and understanding of the previous auction?

 

I personally enjoy reading not only the informed judgements of the panelists but also the assumptions upon which they based their informed judgements, even if those assumptions are not mine...or are not agreed to by others on the panel.

 

Then sometimes I learn: If the previous auction meant what he thought it meant, my bid should have been (X).

[lalldonn]

With equal length, or 2-3 in the majors, it's normal to give a preference.

The 2-3 part is debatable at best. But it would probably make for a more interesting study than this one.

[Stephen Tu]

The 2-3 part is debatable at best. But it would probably make for a more interesting study than this one.

 

True enough. I did an initial sim of this, it suggested it was a tossup, maybe .5% in favor of spade pref, 44% no diff. But that was with 6-4s still bidding 2h. If partner passes with 2-3, do you just bid 2s with those? What if partner can have a stiff spade? Give me some params, I'll rerun on Monday.

[aguahombre]

Even if preferring the 5-2 fit to the 4-3 is debatable; and even if we have to take a hit when responder is 5-5 in the majors ---for those of you unsure whether 2H was intended by this partner as forcing --- it would be a good hedge.

 

For that matter, being unsure and having limited our hand with the 2m rebid, it might not be so bad to hedge with a raise to 3H if we are 4-6 in hearts and our minor.