BillPatch

Particularly playing with a systemic weak NT vulnerable, so that partners one of a minor shows either an unbalanced hand or 14+ balanced points, an invitational bid in two of a minor should allow you to end up either in a ♦ contract, allow a heart preference with 3, or choose a NT partial or game. In modern KS, a diamond pref shows this hand (9-11 HCP, 3 ♦ and 4-5♥). two of the other minor shows 9+ points and that suit. Otherwise, a more artificial weak NT system might use XYZ. (5-8 hcp hands would normally rebid 1 NT, even without a club stopper.

With 14.35 Kaplan and Rubens(knr) points, this is obviously weak enough to downgrade. However, it is anti-field, as point-counters will choose the normal strong NT. Some experts will almost never downgrade for this very reason; they expect to gain matchpoints in the play.

I agree with Fluffy. This is a strong 23.85 knr hand, stronger than the average 23 hcp average balanced hand. Unless partner has a ♥ one-suiter, 2NT is too weak, one of suit also will miss many games and slams. (knr -- Kaplan & Rubens points).

[hv=pc=n&s=saqhk532da5cjt853&d=e&v=0&b=14&a=1cp1dd1s]133|200[/hv] I have a good hand. What do I bid?

It should be noted that the majority of the competition on BBO is scored at IMPs pairs, both in the main playing room, the relaxed lounge, the ACBL and BBO masterpoint awarding tourneys. Novices and beginners who want more info on imp pair strategy who plan to play here on line may search this forum for advice, or ask a new question.

Executive summary: Ran third sample of 20 on 3 options for responder's rebids. Pass now clearly leads other choices in Bayesian probability. False preference barely clings to second place. It occurs to me that it might improve results for the false pref if we manually adopt the Lawrence treatment of showing 16-17 hcp in rebidding 2 NT by opener after responder's preference. (Did make the adjustment several times in first trial.) Trial III In this sample of 20 Pass beat 3 ♥ rebid by 45 imps (2.25 imps per board), Pass beat 2♠ false pref by 52 (2.6/bd), Combining 3 trials: Pass leads 3♥ by 53 imps over 40 boards(1.325 per board). Pass leads 2♠ by 60 imps over 60 bds (1/bd).

I set up the sim specifying that Jack would chose from the subset specifying the modified forcing NT responders hand as South and randomly generated hands in the other seats that matched the bidding from the opening bid to responder's rebid. To prune this new subset, 1. I let Jack actually bid the hands to the point of responder's rebid, and 2. verified that the hand prior to the opener satisfied my idea of a first seat pass. (Jack set for BWS fairly new version in both directions. Let Jack bid to decision point. Threw out hands that Jack did not bid correctly to this point. Input First test variable, letting Jack finish bidding for the other three hands. Frequently jack would put in a takeout double after the false preference. Once when the takeout was advanced to 4♦ I made a penalty double good for +800. When advancer made a penalty pass in ♠ or tried 3♣ I showed my true preference. Opener several times took this to game in ♥. Jack did not chose to intervene after responder's test second round pass, or the test second round 3♥ rebid. After the bidding was over I let Jack make lead, then found the double dummy result from there, (after checking that the W hand had an actual dealer pass.)

Pass. and unless partner acts, pass on next round. If opener raises ♥ my K there is misplaced. If he rebids 1 NT, both the ♥ and ♣ in my hand are bad. (♣ even split, minor honors under opener, ♥ K short in front of stronger hand, so often offside.) penalty double of 1 NT should show values/length in responder's suit, shortness in opener's. Without double I expect partner will often lead a diamond(I could have made a one level overcall if I had the other pointed suit. I would expect a good score. Incidently, a normal first round T.O. shows at least 4 cards in each of the two unbid suits.

Summary: Mea culpa. (My error). My efforts to simulate the given responder's hand and auction and auction on Jack reveal that the 3♥ raise on responder's rebid is a perfectly reasonable alternative. Also, among the responders the false preference slightly leads pass, which slightly leads 3♥. A much larger sample size will be required to reach a significant results between each pair. Replaced low diamond with the J♦ so that Jack would read responder as a 1 NT in auction. Jack considered actual auction as still "impossible". So I ran starting with opener North in first seat and threw out hands that the hand that West had an opener. Auction: P 1♠ P 1NT P 2♥ P ??? First I ran a simulation of sample size 20 comparing my suggested false preference to the auction given in the opening post of this thread. False preference led by 43 imps(2.15/ board.) Since 4 ♥ made so often my next trial I added responder's second round raise to 3 ♥. Repeated with a trial size 20. Result: Comparing responder's rebids: Pass beat 3 ♥ by 8 imps (0.4 imps/bd). Pass beat 2 ♠ by 35 imps (1.75/ Bd). 3♥ beat 2 ♠ by 16 imps (0.8 imps/bd) Combining trials: 2♠ leads pass by 8 imps over 40 bd (0.2 imps/bd), pass leads 3♥ by 8 imps over 20 bd (0.4 imps bd. Looks like a 500 sample needed to determine significant result between any these choices. By the end of the summer I intend to learn enough Windows 7 computerese to simulate using Thomas Andrews Deal, or to do it with Dealmaker Pro on another computer. Bill Patch

The only rational choices are pass and a false preference to 2♠. Even with a slightly sound opening style, (rule of 20, 2QT)we will often go down on the 11-13 hcp hands in ♠. If I need to make up ground, game heavily odds on if partner can rebid NT, (16-17 hcp)or ♥. I think it is slightly imp negative, but the high skew would often be good, so I might try it 30% of the time. In a short imp pairs such as on BBO these swing boards are often useful.

advancer asks for 2nd suit by bidding 2♣, shows own suit at two level, raises spades preemptively, asks with 2NT, or makes a penalty pass for a ♠ lead.

Kleinman's proposed "Supernatural" features one suiters (4) at the two level, a double to show the 3 two suiters with ♠, 2NT for minors, 3 of a min0r that suit plus hearts, 3 of a major strong one suiter, 4 of a minor weak.

1. Assuming 0-36 hcp any 5332, 4432, or 4333 rounded to nearest .o1% 5♥ 3.47%, 4♥ 20.73%, 3♥ 47.37%, 2♥ 28.42% total 99.99% Calculated to exact number of hands. 2. Thomas Andrews has simulated the outcomes of the auction 2NT all pass and 2nt pass 3nt for various combinations of honors. double dummy using his program Deal. For xxxxx Axx Txx xx for a sample size over 600 he computes 3nt makes 35.6+-1.4% and 2NT fails 21.8+-1.2% Therefore it was worth a raise to 3NT at imps only when VUL I only ran a sample of 20 reps 20-21 hcp the given NT dist for N and the given hand for S For the auction 2nt all pass 9+ tricks made 50% exactly 8 45% and one down 5% The good spot cards on my simulation provide a non-random bias from the Andrews result, but my low sample size provides a fairly large random error Only reaching game on the superaccepts reached 7 4♥ making games, losing to the direct 3NT raise 10.5 to 9.5 at MP. The clear winner was the jacoby 3♦ followed by 3nt, making 13 games, going down 7 times, only once for -500. at MP beat 2nt 65-35, the direct 3NT raise 60-40, and only reaching game on superaccepts 57.5-42.5%.

A short simulation of 30 reveals that the contract of 4♠ makes 47% for a net gain of 1.5 imps per board in an imp match. (With double dummy leads it only makes 40%, but that assumes E will not lead partner's suit with a small doubleton, rather than lead away from an ace tenace or six small in an off suit. Vulnerable at Imps, a 40% game still averages 0.4 imps per board.)

This book is most interesting to me because it attempts to use computer simulation to statistically analyze a monte carlo sample of bridge hands to model superior bridge play. monte carlo is a statistics term for sampling from a random choice, as in statistics of the gambling tables at Monte Carlo. I studied computer monte carlo simulations in both engineering school and an MBA program, and enjoy seeing their applications outside the computer world. The two masters, David Bird & Taf Anthias, present the revolutionary suggestions generated by this experiment. The old notion that the best leads against notrump, barring holding a good 3 card honor sequence, is fourth best from the longest and strongest suit, is shown to be passat. While retaining the framework of standard leads, the leads that best utilize both defensive hands usually attempt to hit partner's suit, unless leader's hand suggests otherwise. If the declaring side has not investigated suit play the leader should strongly favor the major suits, usually preferring three card suits and doubletons. Four card suits led by one or two honors should not normally be selected, though a four card major is usually as good as a five card minor. Two card honor sequences in a major suit, with or without additional spot cards, are good leads compared with fourth best. When the opponents show suits, opening leader usually avoids them. If responder tries stayman and gets a negative response, majors are still highly preferred leads. If partner overcalls, or opens a major, it suggests a strong lead. It is relatively easy to gauge one's progress in learning through this book and its successor on suit contract leads, because each short chapter is followed by a thorough quiz on similar leading questions, each with the statistics of the suggested leads. I believe it has similarly affected my leading prowness with relatively little effort. I recommend this book for intermediates through experts. I had a slight difficulty in applying the leads in this book in the case of ace leads. The authors do not employ the standard American convention that the lead of an ace against notrump demands an unblock, otherwise third hand signals count. They note the merit of this convention, but fail to warn that it is incompatible with 90% of the ace leads recommended here. Bird in his book on signaling prefers the convention "Ace lead for Attitude, King for K©ount" from AK + suits against notrump contracts. A reviewer on Amazon noted that since he studied this work in his bridge play on line he defeated one quarter more notrump contracts, and gave up an average of almost one overtrick per contract he failed to defeat.

Advancer has 3 tries to sort out stoppers to reach 3NT: bid 3NT, cue 3♠, or reverse to 3♥. 4 possible messages. 1. I have the full ♠ stop. 3NT 2. I have a half stop(K,Qx or Jxx). Lawrence has suggestted that a cue over an overcall suggest this. 3S? 3. I have no stop. 3H? 4. I have a ♥ suit. 3H? Opener's ♠ rebid reduces the need for message 2. overcaller might have doubled on the second round to suggest a ♥ suit, reducing the need for message 4. I vote for 1,2,3 for 3nt, 3S and 3H, respectively. If partner then rebids 3NT after opener passes, I would pass. After opener doubles 3♠, overcaller can accept 3NT in 3 ways. 1. bid 3nt 2. pass, then accept 3NT 3. RD, then accept 1 would be strongest suggestion for 3NT. 3 weakest? I would only bid 3NT directly with full stop A Q J 10 XX or better clubs so that they will run after finesse onside at worst.

Your hand South qj5 qt5 qj5 q964 Bidding N 1♦E 2♣ S ??

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A short (10 board) simulation yield a win for 1 ♥ 1.3 imps/bd over pass and 2.2 imps/bd over 2♥.

Am I correct that 3♠ cue implies half stop? If responder had full stop NT interest he might bid NT. If opener has full stop he might bid NT himself.

Another conventional use of 3♦ over the 3♣ opening is artificial asking for a stopper. 3 of major shows that stopper, 3NT the diamond stop, and 4 clubs no outside stopper. A safer way to reach a good 3NT.

Rosencrantz and Guildenstein were charactors in Hamlet. The double was invented by Jorge (George) Rosenkranz.

3♥ shows 4 card support, and more narrowly limits hand. After the 2♠ cue, not knowing fit, partner will show stopper if he has it. Axx good for slam, KQx the dregs. If partner prefers ♦ you will know double fit, but little else. After raise, if partner bids new suit you know it's a slam try, and immediately ask for key cards. Bidding space saved by cuebidding wasted because of poorer limitation of your hand.

I prefer the J of ♠, second choice 6 of ♠. I would be less enthusiastic about falsecarding with another ♠ opening lead. I do not like the idea of leading from the major tenace in, would lead J of ♥ at gunpoint, if I believed gunman was serious. As bad would be to lead one of their minor suits, perhaps opener has a three card ♦.