uresh

I misspoke in my previous post. When vulnerable at IMPs, we should bid game directly with any 9-count (and no major interest). The invite is better at matchpoints or non-vul at IMPs with 4333 or 4432, and at matchpoints even with 5332. The assumptions are that opener accepts with any 16 or 17 count (as you have noted, conservative acceptance fares worse), and RHO does not have a hand suitable for action over 1N. I have attached below the detailed analysis for 4432 shapes. Can share the analysis for the other shapes if needed. Analysis for 4432 9-counts: Bidding 3N vs Inviting -------------------------------------------------- The only hands that matter are when opener has a 15-count. On all others, you will be in game either way. (There is a slight benefit of concealing opener's point range when responder bids 3N directly; hard to quantify.) In a simulation of 10,000 hands, when responder had a 9-count 4432, opener had 4364 times. Of these, the hands made 9 or more tricks 1475 times, 8 tricks 1733 times, 7 tricks 839 times, and 6 or fewer 317 times. At BAM or match-ponits, you gain when the hands make 9 tricks, lose in the other three, for a net loss of 1414 points in BAM, or 0.14 pts per deal. Vulnerable at IMPs, you gain 10 IMPs when making 9+ tricks, but lose 6 IMPs when making 8 tricks and 3 when making fewer than 8, for a net gain of 884 IMPs, or 0.09 IMPs per deal. Non-vul at IMPs, the gain for making game is 6 IMPs, and the losses are 5 IMPs when making 8 tricks and 2 IMPs when making fewer, for a net loss of 2127 IMPs, or 2.1 IMPs per deal.

Thanks for the replies so far, and keep them coming :-) Siegmund, I am glad I looked at your articles. Looks like we both started with some of the same questions, but you have done a lot more work than I so far. Many of your conclusions validate my independent work, but I reached a very different conclusion on what to do with balanced 9-counts without a 4-card major over a 15-17 NT. My analysis, along similar lines as yours, indicates that it is better at all forms of scoring and vulnerability to invite with these hands unless you have a 5332 shape, in which case you should bid game directly. I will try to write up the analysis and share with you.

I have started doing some analysis, using a hand generation program and Bo Haglund's double dummy solver, of some common bidding scenarios. My aim is to quantify and advance our collective knowledge in the field. I am looking to answer questions like, for instance, should we use stayman over 1N with a 4-3-5-1 and a 5-count, at match points or at IMPs? Before I invest too much time in this, I wanted to check if anyone has heard of similar published work? I have seen Bird and Anthias's excellent books on leads based on simulation, but nothing so far on bidding. I would also like to know if there is interest in this type of analysis. If so, I would welcome questions and scenarios to analyze. Finally, would the BBO forums be a good place to publish the results? Any other thoughts or ideas?