Siegmund

I have noticed that I usually know a couple tricks ahead of time if a squeeze is going to work, because the GIB makes a "gift" discard that was in fact going to be forced a few rounds later. I could be convinced that it really is random, and it just catches our eye because a human (at regional or lower level) would always play the card that gave an imperfect declarer a chance to fail to properly execute the squeeze or endplay, so half the time GIB's play looks normal and the other half it looks like a silly mistake. It annoys me, because it means I am getting a 50% board in a robot tournament that would have been a 70% in a weak live game -- but usually if GIB makes a fatal early discard it's because he really was going to be doomed unless I did something really stupid. From a programming standpoint, I don't see a good way for GIB to evaluate what kind of mistakes it thinks a human declarer would make in situations that even a 'dumb' computer would never get wrong. It certainly doesn't seem like a priority, compared to the other improvements to GIB's bidding and play that could be made.

Re the Walsh, I think GIB has always done that when sufficiently weak, though I don't know offhand how weak 'sufficiently weak' is. It's one of those things I don't notice since "everyone" in my area does this in live games :)

At IMPs I am a timid passer. A speculative double is tempting. It might even work half the time so I might try it at MP. In my opinion 3NT is outright suicidal. We rate to have almost exactly half the deck and we don't have much prospect of a second spade stopper. 4H is a gamble on partner having a maximum and us getting in in time to pull trumps before E ruffs diamonds or W ruffs spades but I can imagine it working say 25% of the time, and pushing the opponents to a speculative 4S a similar amount of the time. 3NT doesn't push them to 4S.

Thomas Andrews has some articles about best point counts for suits and for notrump (they are not the same; HCPs are sort of halfway in between.) "Using it for future sims" isn't really an option if our task is to evaluate responses to a standard 15-17 notrump -- though, for instance, opening with HCP and using a specialized point count to decide whether to accept an invitation is.

I had to go back and look at my article again. With 3343 or 3244 shape it is pretty much a tie, at matchpoints or NV imps, whether to invite or not, if your rule is "pass with 15, go with 16." If you have a more precise way to decide whether to accept an invitation, that will make the invitation more appealing. If you used slightly different restrictions on opener's hand, that can make a difference too. I would not argue either way if someone wanted to invite with 3343 or 3244 hands and 9HCP. (But from a system design standpoint, if I am going to pass all 8s, and bid 3NT on all 10s and the 3352 9s, I think I have better things to do with the 2NT rebid than use it for an invitation.) Vulnerable at IMPs, I would be surprised if it was right to stop in 2NT with 15 opposite 9. Usually with 24 it is better to be in 3NT than in 2NT (maybe not better to 3NT than 1NT - but once you have invited that isn't an option.)

Yes, double dummy analysis can be used to inform bidding decisions. It is easier when you have a fixed system and you want to ask, which is the best bid on a given type of hand. (4-3-5-1 5-count in response to 1NT? Yes, use Stayman. Also 3-4-4-2, 3-3-6-1, and several other shapes you might not expect.) Choosing among several meanings for a bid is hard - if you make one response better maybe you make another worse. Any experiment that requires letting two hands vary at once rather than just one is also hard. BBO is certainly one place you can make people aware of your findings. The analyses I have done in the past I posted on my own website. Of course I am very lazy about finding time to write up the results nicely after I run an experiment so I have not posted much in awhile :) http://taigabridge.net/articles/dd/

Great replies so far. (And I am not surprised your answer is that it's more about giving more hard decisions to the opps, and guessing right more often in close cases, than it is actual technical differences.) A rule of thumb that has been around for years is that the very best players are 1 imp a board better than A players, who are 1 imp better than decent Bs who are 1 imp better than decent Cs. (It falls apart at the very bottom where there is almost no limit to how bad you can be.) There is an accompanying rule of thumb that the final margin of an n-board team match is about Normal(margin*length, 6*sqrt(length)) -- a 45% chance in a 7-board match, by that rule, amounts to 0.28 imps per board, and predicts a 41% chance for you in a 24-board KO match and a 35% chance in a 64-board Spingold segment -- which maybe isn't so far from what happens when a team like yours hits a top seed. When filling out the fantasy brackets there are a lot of late-round matchups that feel like almost blind matches. I guess I was imagining there would be a dozen or more teams a bit closer matched. . (0.1 imps a board makes a 64-board match a 55-45 proposition.) Sounds like you have a big edge in the fantasy brackets if you know the players well enough to know which of those "ties" are really 60-40 shots! Is there much that an almost-top player can do, besides "keep playing a lot against good opposition", to narrow that gap at the very top? Sure makes it clear why learning how to pass a discreet signal is so tempting. Getting one key close decision right per session would be enough to tip the odds and make someone a winner. Fortunately it seems that cheaters always get greedy, and want to maximize their short term profits.

PhantomSac, posting in another thread, made the following comment, that might be a bit surprising to some of the rest of us: "People like me... "fringe top pros" if you will who are outskilled by people like Helgemo/Meck and outcheated by other people." It got me wondering what is a 'fringe top pro' and how much of a skill difference exists among the top pros. For small-time 'pros' who make their living teaching and playing the odd regional event vs. playing in the Spingold, sure, we know that the national level pros have an edge on us, and sometimes we even can eludicate where that edge is. (I know that even on my best days I don't always cash my tricks in the right order for a double or compound squeeze, and I know I have some other blind spots in choosing the best line among several. I don't feel like I am consistently outbid by the players I see in the magazines.) But I don't see technical differences very often among the Spingold finalists very often -- not at all like it was 50 or more years ago. If someone asked me a question like "who plays better, Hampson or Passell or Cheek?" I would just sort of shrug. ARE there "big" differences even at that level? This was actually one of the more interesting parts of Brogeland's and Woolsey's recent posts -- describing some plays they believed a true top expert would always find, but a garden variety sorta-expert would not. I hope we will see more of that when Woolsey's "survey" comes out. If Justin is willing to comment here, I'd love to hear from him. Likewise anyone else who rubs shoulders with the top rung often.

The quality of the conversion is highly variable, depending on the package. tth fails entirely - chokes on user-defined commands as undefined commands. latex2html will have the same basic problem, though more curable, in that you can teach it how to interpret user-defined commands by writing translation routines in perl for it. tex4ht sort of succeeds. For files written using 'grbbridge', htlatex filename.tex works quite well on everything except spade bids (!). It chokes on the fact that \sp is a synonym for the math mode superscript symbol, and turns \sp{4} into '^4' rather than '4♠' despite the \renewcommand in my package. I expect other custom packages will have a similar experience.

It is odd that the General Convention Chart psyching restriction hasn't been extended -- it still says "psyching of artificial or conventional opening bids and/or conventional responses thereto. Psyching conventional suit responses which are less than 2NT to natural openings." So apparently it really IS their intention to forbid psyching a natural response or rebid to Midchart conventions only (and to relax the restriction on psyching conventional responses to natural openings, on the Midchart.) That is a subtle distinction I don't recall seeing before -- but as I typically go years at a time without seeing a single Midchart event, I didn't pay much attention to the wording of the Midchart for a long time.

Does this mean that it is legal to psych a GCC convention under the Midchart, only illegal to psych a Midchart convention? The wording has changed at some point since 1997 -- once upon a time, it said psyching conventional openings, and psyching conventional responses, but it now has been extended to rebids, and, apparently, to natural responses after conventional openings.

Not everyone would equate being responsible with having 2 kids and another on the way, I daresay :)

This week I received my thrice-annual report from my district director. I was surprised to see it say that a motion to change the ACBL's Law 12 election -- follow the rest of world in adopting weighted scores instead of "likely / at all probable" -- had passed 25-0 and was due to take effect next January. I couldn't tell at first glance if it was an item that required a second reading in Denver or not... but whether it does or not, I was startled that the proposal wasn't attracting any discussion here or on BW. (Nor has it after it passed, apparently.) I appreciate the value of having the rules be the same everywhere - but confess I will be very sad to see L12 change. When I very first read the laws and became a club director 20 years ago, I remember thinking that rule was a beautiful encapsulation of the spirit of the whole book, as close to a perfect law as there could be.

Whatever meaning you give to 4S its going to be incredibly rare. Do you have a better idea than exclusion? (I have never leapt higher than 4m in my life after an inverted raise. I've never bothered to give this bid a meaning at all. But if a partner had agreed exclusion and this sequence came up that's how I would take it.) I don't play exclusion at all with very many partners. None of its uses is exactly frequent, and in the "common" auctions like 1S-3S, 4C-4D, 5H, there are competing meanings which sometimes make more sense in the context of the cuebidding style. Before anyone played exclusion, odd jumps one level higher than splinters were control-asking bids. Now those I have actually used one or two times in the 20 years since I learned about them. :)

Know nothing about WordPress, but I would guess most of the web apps you see to allow you to convert single math formulas from LaTeX to HTML do not have "real" LaTeX compilers behind them, but are scripts someone has written to interpret many of the basic built-in commands. I would expect most of them to fail if confronted with a single user-defined command, and all of them to fail if you asked them to do something requiring a special package. I expect your choices are either writing your own bridge-related conversion script (handling the suit symbols and converting tabular environments into HTML tables will get you 90% of the way there probably), or seeing what happens if you use one of the general-purpose LaTeX to HTML converters out there. I have no experience with htlatex, tex2html, or their variations, though: it's not a conversion I have to do very often.

That's a traditional meaning for 1m-1M-4m (in North America), but not for 1M-2m-4M. *** As to the original question, I would sharpen MrAce's answer to *exactly one trick* too strong to open 4M, after which partner bids exactly as he would after a 4M opening. Not perfect but no accidents that way, at least.

It's not a scientific survey, and I do play in a relatively oldfashioned part of North America... but don't be surprised: I can't remember ever having a partner propose 2-level takeout doubles over a strong notrump when we filled out our card. I do know a couple of weak notrumpers who do it. I've had plenty of people play it as takeout against me -- almost all of them beginners who had no idea that 1NT-2D-X might be different than 1H-2D-X. The ones who haven't yet been taught Stolen Bid by their friends. Heh. (There are a few good regular partnerships who do it, but they are an invisibly tiny minority where I am.)

Tried one more experiment - limited opener to being 3(433), 2(533), or 2(443), rather than allowing all the 2542 and 2263 type hands. This sharpened the differences more: C losing 0.64 imps, D losing 0.70 imps, S losing 1 imp, H losing 1.16. Setting the contract goes from C 7%, D 6.5%, S 4.3%, H 3.3%. (Not allowing 2254/2245 removes a whole lot of the hands where a heart lead is successful - which pretty much needs opener to either have a doubleton or not have an honor.)

The answer is somewhat sensitive to the sim conditions. I interpreted responder as never having a singleton, rather than just not 5044. (The truth is somewhere in between; some but not all 5143s will bid the 4-card minor.) At MPs the club was a clear winner by a small margin (71% chance of still being able to achieve par after a club lead, vs. 68% for a diamond, 66% for the spade, and 64% for the heart). At IMPs it was pretty much a tie between a low club and low diamond, with an average loss vs. par of 0.98 imps. A low heart was -1.05, and a low spade was -1.18, almost as bad as the DJ or HJ. I had a 6% chance of setting the contract with a heart, diamond, or club, only 4% with the spade. If dummy is not going to have a singleton heart, the chances of running hearts get far better (partner has 3 hearts, or has 2 high hearts and good enough diamonds the DJ is an entry). Correspondingly the chance of a spade being safe is hurt when opener can be 3433 (and I think he can be.)

My first thought was I might do better with diamonds than spades -- pull all the trump, ruff a diamond, claim if they are 3-2, use the HJ to try to get 2 entries if they were 4-1 -- but I think AK and club ruffed high line is better now too.

♠Qxx ♥AJ ♦A9xxxx ♣xx ♠AKJxx ♥Kx ♦Kx ♣AKQx Simple fast auction: 2C-2D, 2S-3S, 4NT-5S, 7S. ♦Q led. Obviously you have to dispose of the small club in your hand. And if everything breaks well it is easy. Got a few choices which bad breaks to be prepared for...

Which experts? :) There is a lot more variety now than there was 20 years ago. Not so much with the 2/1 base, as with the selection of bells and whistles added to it. The Hardy-inspired style remains popular out my way, but a bunch of "dead" ideas like single raise constructive have found a new life and become popular again especially in the East. There is a lack of new serious 2/1 system books of any quality - Thurston's 25 Steps to 2/1 is not "Expert"-oriented, and while Volume II of the Hardy includes many of the newer toys, you wont find many people playing the whole system that way. For the modern approach to slam bidding, the 3-part articles by Fred Gitelman circa 1999 have stood the test of time well and should be on anyone's required-reading list. Some of the new toys on the horizon, like Gazzilli, are exciting but have still been adopted by very very few US players. Standard is, as always, a moving target. Chaff to wheat ratio is quite high on the internet too, so not sure there really is a better approach than exploring and finding out which of the new gadgets you like.

Hm. I estimated 70% too -- but on the assumption that almost everyone in my club is getting to 4S (even the ladies with walkers are bidding on 5 HCP and a 5-card suit now, it seems) but most of them finding a way to lose 4 fast tricks.

Playing a majors-first style, this jump (and 1m-1M-1NT-3om) tends to be 6 of the minor and only 4 of the major. If I had 5-5 I would have FSFed/NMFed to look for the 5-3 fit. And in my preferred style, all of these jumps are GF and all the invitations go through FSF/NMF - but I realize most of the 2/1 world does it the other way round. Absent discussion I would play a random pickup partner for a strong 5-5, but I wouldn't expect a good random partner to spring it on me.

I daresay Max would claim he wasn't "varying" anything -- that his agreement, in all situations, was that the cheapest bid in the suit his opponent opened was top-and-bottom, "and the ACBL requires me to play the same system over in-turn and out-of-turn opening bids" :) I would be inclined to rule in his favor, too. I wonder what thinks a 2H or 3H opening followed by 4H-out-of-turn shows. One of them is going to be a stopper ask with a long minor, the other... um.... I have no idea! And yes, if his partner figured this out, his partner probably ought to alert, as we generally alert so-called "invisible cue bids" though we don't alert most meanings of (legal, sufficient, in-turn) cuebids.