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rhm

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Everything posted by rhm

  1. Since when is 31(45) balanced or semi balanced? You asked for a simulation with East being balanced or semi balanced. I obliged and now you complain? Rainer Herrmann
  2. In general if two balanced hands bid 3NT with a combined 25 HCP the chances of making is around 50% I did such a simulation with the West hand as given and East being balanced or semi balanced, 10 HCP and 2 or 3 cards in hearts. Result(1000 random deals): 3NT made on 604 deals (60.4%) Average number of tricks: 8.743 Single dummy with no revealing auction like 1NT-3NT the success rate will be even higher because of declarers advantage in 3NT Rainer Herrmann
  3. 2NT (assuming that shows now more than 14) Rainer Herrmann
  4. A misconception. K&R is not the holy grail of hand evaluation. The method does reasonably well evaluating hands ending in trump contracts (subject to finding a reasonable fit of course). It does not so well for hands ending at notrumps. With regard to the actual hand K&R only proves that the hand is more suitable for notrumps than for a suit contracts, where it's worth is less. So opening a strong notrump (15-17) is quite sensible, opening a weak notrump (12-14) much less. Rainer Herrmann
  5. The question you need to raise is not whether garbage Stayman makes any sense. It does. The question is how many sequences do you want to reserve, finding the best contract when responder has a weak hand, how many for invitational hands and how many for strong hands. The answer may somewhat depend on the range of your 1NT opening. Playing a strong notrump (14+-17) I do not want to allocate that many sequences solely for garbage, which is usually done at the cost of showing invitational hands. With garbage I can only continue bidding 2♥ over 2♦ after Stayman. If I bid anything else I have either an invitational or a strong hand, depending on the bid I make. Rainer Herrmann
  6. I play Polish Club but neither do I rebid 5 card suits, unless it is a very strong major and might be best even opposite a singleton. This is no question of what bidding system you play. In a strong notrump context, opener will usually be 12-14 balanced or if unblanaced find another bid. But that is why it is important that the bid is constructive and the suit is good. The alternative in standard to negative double and then show the suit a level higher thereafter (or miss game) is surely worse. I do not get this point. If I have a good suit and an invitational hand I need either a fit or extras with opener for game to be worthwhile. Of course there is room for judgement by opener. However, with no assurance of a real fit and a possible minimum I do not want to force him. So the above is exactly the reason why your argument is not a sign of weakness but of strength for NFB. Rainer Herrmann
  7. I never claimed that there is no difference. Why is it ridiculous mentioning a simple fact? If you would play new suits forcing after a notrump opening and an overcall your game and slam bidding would surely improve as well and if you play strong notrump you need less to hold game forcing values. Appearences are deceptive I am completely aware that forcing does not mean the bidding could not die on the next round. My analysis is based on the notion that I would like a new suit bid at the two level after an overcall to be forcing only if I have game forcing values. If I do not have them I am clearly at a disadvantage if I force my partner to bid again and the whole point was it is not impossible but unlikely to hold game forcing values when RHO interferes but does not preempt. You yourself mention the disadvantage of getting too high. Also if I force, my partner has also more difficulty to differentiate his strength since he can not pass with a minimum hand. By the way NFB is no hindrance to reach game or slam when hands fit well. I have had times when I bid a new suit nonforcing reaching game where my counterpart in the other room made a negative double and missed game. This shows that you have not understood NFB. This is not a question of version, but good bidding or poor bidding. NFB are not an excuse to bid on bad suits or on a weak hand. Of course they include invitational hands. They are not sign-offs. NFB always show a constructive hand with a good suit, but less than a game force. Should we eventually defend, they tend to be good lead directors. The less you have the better the suit. The HCP range is 7-11. With less and without a fit you pass the overcall at the two level or if your suit is poor you might make a negative double. Opener is well placed. As I said my experience is that at least 90% of the time when I bid a new suit as non-forcing after an overcall other pairs, who do not play NFB, make the same bid, but now the bid is unlimited and forcing. Rainer Herrmann
  8. Your cynic is quite wrong. Where I play, Negative Free Bids are quite common at the two level only and very common among Polish Club players, where it is almost an integral part of the whole system. By the way when partner opens 1NT and RHO overcalls almost anybody plays new suits at the two level as Negative Free Bids. I agree completely with the first quote above. Once your RHO overcalls - not preempts, in which case new suits remain forcing - you are not that likely to hold a game force without a fit with your partner's suit. My experience is that when I make a negative free bid, others, playing this bid as forcing, make exactly the same bid, only they can not stop at the two level and quite often get too high on minimum values or a msifit. Most players are understandably reluctant to pass with a constructive hand and a good suit when RHO overcalls, even if they do not have game forcing values. After all LHO might raise his partner. First: Most play NFB only at the two level. Once RHO has overcalled I do not play weak jumps in new suits to the three-level. They are game forcing with good suits. (Of course transfers are a very sensible alternative) So your scenario arises only if 1) you have game forcing values, unlikely in the first place 2) no fit for partner 3) no good suit of your own. Then you intent to double first. Now if the overcall is advanced you might have to judge between bidding your 5 card suit but with values for game in the knowledge opponents have a fit or doubling again. Your claim that the costs are huge is greatly exaggerated, probably because you have little experience with NFB. You also underestimate the value when opener knows from the NFB that the hand opposite is limited in strength. I can not remember ever having got in trouble when holding a game forcing hand. The method is quite robust and that opponents can exploit NFB is a myth. It is also a myth that most IMP matches are decided by superior game or slam bidding. Partscore battles matter too and are much more frequent, when opponents overcall, and a lost partscore cost on average about 50% of a game or slam swing. Rainer Herrmann
  9. I certainly agree with you in principle that HCP are not the sole issue, when looking at game in a trump contract. Controls, particularly aces, distribution (side doubleton, good 5 card suit etc.), length in spades all play a more significant role than the odd HCP in an already tightly limited hand. This is debatable. Of course weaker players tend to be better at declarer play than defense, but the overall level of play tends to cancel out, as long as both sides (defense and declarer side) have similar levels. The question is really what tactic a good pair should employ when playing against a weaker pair in a matchpointed event. Time and again I have seen the stronger being overconfident about their abilities, getting them a poor score against weak pairs. When 4♠ requires expert play and a slip in defense to make there is no need to bid the game, 170 will beat the field handsomely. The danger is going down in 4♠ when the field is making 8 tricks in 2♠. Time and again I have seen goods pairs scoring badly against weak pairs that way. Rainer Herrmann
  10. I have made already 3 simulations. The last one is not directly comparable, since I only generated deals with North holding a 1NT opening where he should accept. But if you look at the second one (december,15th 12:45) you can deduce from 1000 deals where North does not superaccept you have 843 deals where you can make 9 tricks or more. Therefor on 157 (15.7%) 3♠ will fail (16 deals will already fail in 2♠) So 141 (14.1%) deals will make exactly 8 tricks in spades Rainer Herrmann
  11. I do not write the code I use Dealmaster PRO Rainer Herrmann
  12. For you I ran the following simulation (1000 deals) when North accepts the invitation with the right hands: South hand as given. North criteria for accepting the invitation (always balanced): 1) 17 HCP, exactly 2 spades, at least 6 controls 2) 16-17 HCP, exactly 3 cards in spades, but not 3♠433 if 16 HCP, at least 5 controls 3) 15 HCP with exactly 4 spades or 16 HCP if 4♠333, as otherwise North would have already superaccepted. These are at least some of the North hands, with which I think the invitation should be accepted. Result of this simulation: If North declares double dummy North makes at spades 10 tricks or more on 686 deals ---> 68.6% 9 tricks on 938 deals (93.8%) 8 tricks on 994 deals (99.4%) You see? Maybe you learn something how good hand evaluation improves your chances of making the proper choice. HCP alone will not do! Rainer Herrmann
  13. You should read more carefully. Game succeeds roughly on 50% of all deals, precisely on 479 deals of the simulation. . When opener gets invited, opener will not always choose the right 479 deals, but he should get this right far more often right than wrong. If opener accepts on 600 deals and gets this right two thirds of the time he will succeed in game on 400 deals, while if opener would choose perfectly he would succeed on 479 deals That is 40% of all the deals. Two third of the time is a rather conservative estimate if opener can judge a bridge hand. Note, that if opener chooses the 600 deals completely randomly where he accepts, that is without looking at his hand, game would still succeed on nearly 300 deals and opener will certainly do much better by looking at his hand. Rainer Herrmann
  14. I doubt your numbers. My numbers say that there is almost a 50% a priory chance 4♠ will succeed and more than an 80% chance that 3♠ will succeed. When there is so liitle to choose between passing 2♠ and bidding game matchpointwise, you can bet that inviting will handsomely win. Assuming you invite, I guess the 1NT opener will be right most of the time he accepts and also when he declines. This is not a random guess for someone, who knows how to evaluate a bridge hand. For example if holding ♠Kxx ♥Ax ♦xxx ♣AKQx I would accept, but holding ♠Kxx, ♥Kx ♦KQx ♣KQxx I would decline. If responder simply bids game he would beat you on almost 48% of the hands (479 delas) The middle of the road action of inviting will not beat you quite as often, because opener will sometimes decline and game would have made. But far more often there will be far less wins for you and far more draws when opener declines and 3♠ will make. For example, say we accept on 600 deals the invitation and we will make game on two thirds of them gives us 400 wins and 200 losses, on some of these deals going down more than one. On the remaining 400 deals we decline and we will still make 9 tricks or more 75% of the time gives us 300 draws. On the remaining 100 deals even 3♠ proved too high and we can make only 8 tricks or less, a win for you. So you would win on 300 deals and my strategy wins on 400 deals. In other words your numbers are wrong. Rainer Herrmann
  15. Of course everything can happen and will eventually happen in this game. The Law of Total Tricks is fine when you or your opponents can judge total trump length round the table. Bridge is a game of incomplete information and anyway I do not consider the LAW a substitute for judgement. In this case opponents do not know your degree of fit and only the last opponent will get a chance to hear responder pass after the transfer. I very much doubt that opponents with half the HCP in the pack will invariably balance over 2♠ at MP, particularly when vulnerable. If they balance you can always bid 3♠ and sometimes they will balance and get doubled or go down when nothing makes, because neither side has a nine card fit. Jumping to 3♠ when opponents are not in the bidding, when only you know your side has a 5-4 fit, does not look to me to be winning MP tactics. You may sometimes get a decent MP score going down in 3♠, but I bet your MP score would have been better making or going down less in 2♠. Rainer Herrmann
  16. As I said people have different opinions when to superaccept. Assume the 1NT opener has 4 or 5 spades. The 1NT opener is still much more limited than responder. When responder passes your superaccept you will often go down and this is much more frequent than responder having just enough to bid game over a superaccept and game makes, where responder would otherwise have passed at the 2-level. It is not that under those conditions game will always make or even be a good proposition. It is true that quite often opponents can balance profitably if you do not superaccept and responder is weak, but do they know? Balancing is inherently quite risky If they do balance you can still bid one more for the road. Overall I think superaccepting makes only sense if you have a good 1NT opener and at least 4 card support. You should be slightly more aggressive superaccepting hearts than spades and of course vulnerability for both sides come into consideration as does scoring. Otherwise superaccepting is a losing proposition, particularly at matchpoints, though you will get your occasional triumph. Let's make some simple assumptions for superaccept, which are easy to simulate You superaccept with 5 spades and you superaccept with 4 spades with 16-17 HCP, except when you have 16 HCP and 4♠333 Again I simulated 1000 random deals with the South hand excluding superaccepts for North: If North declares double dummy North makes at spades 10 tricks or more on 479 deals (47.9%) 9 tricks on 843 deals (84.3%) 8 tricks on 974 deals (97.4%) If South is declarer 10 tricks or more on 451 deals (45.1%) 9 tricks on 821 deals (82.1%) 8 tricks on 963 deals (96.3%) North makes double dummy at notrumps 9 or more tricks 259 deals (25.9%) 8 tricks on 497 deals (49.7%) 7 tricks on 788 deals (78.8%) Compare this to my previous run. The difference is marginal, given that any simulation run has some statistical variations. Rainer Herrmann
  17. No they do not. . People differ when they superaccept. If you superaccept spades only with 4 spades and a maximum only a small percentage of North hands will qualify when you hold six. My guess is at best 10% I doubt it affects the outcome very much Rainer Herrmann
  18. This is easy to simulate. I used 1000 random deals giving North a balanced 15-17 HCP Result: If North declares double dummy North makes 10 tricks or more on 495 deals (49.5%) 9 tricks on 820 deals (82%) 8 tricks on 972 deals (97.2%) If South is declarer 10 tricks or more on 467 deals (46.7%) 9 tricks on 802 deals (80.2%) 8 tricks on 965 deals (96.5%) North makes double dummy in notrumps 9 or more tricks 249 deals (24.9%) 8 tricks on 498 deals (49.8%) 7 tricks on 775 deals (77.5%) Transferring to spades looks right. But passing 2♠ looks too conservative even at matchpoints. Simply transfer and raise 2♠ to 3♠, assuming you can not show shortage in an invitational hand. The big question is whether you should correct, should opener suggest 3NT over 3♠. Double dummy that is correct, but single dummy at matchpoints this is closer, but probably still correct. Rainer Herrmann
  19. I do. All well and good consulting partner and keeping the bidding low. If you rebid 2♦ it will be difficult to convince your partner that hearts can play opposite a void and that you have a good hand. Jump rebidding your major is a very practical bid. I can see many hands where 4♥ makes and 5♦ is down when partner has 4 cards in diamonds and shortage in hearts. I think it should be natural, but partner is allowed to correct back to spades. Then it will turn out it was a slam try with a very strong spade suit later. Bid 4♥. What else? You do not want to play diamonds. Bid 4♥, but I do not like this auction. Rainer Herrmann
  20. What is the point of playing double as a penalty double of 1NT if the opponents are not in 1NT any more? You can play double showing a balanced hand, in which case you should still define what it says about West heart length. I am pretty sure you would not suggest DBL of 2♦ if West had a balanced hand with a fifth heart. Why should North bid 2♥ over the DBL? When is East supposed to bid 2♠ or 3♣ over the DBL? With hearts it seems more prudent to wait and double then, but West is a bit weak for this action. Rainer Herrmann
  21. I did not miss your point, in fact I quoted your first post in full. However you missed my point, namely that bidding with the West hand, given that South shows hearts is the sure sign of a loser, no matter what the outcome on the actual deal would be. The risks are far higher than the potential gains Rainer Herrmann
  22. I try to be quite clear with my statements. In case you did not get it: I usually look at 13 cards when I sit down and bid at the table and I recommend some caution when judging the bidding of others looking at 52 cards instead. I ran a simulation creating 1000 random deals giving West and East the hands they have and stipulating that South will have 5 hearts and North a balanced hand with 10-12 HCP. Double Dummy Result: On average West would make 7.8 tricks per deal at notrumps 3NT would make on 234 deals, that is a 23.4% chance. Now West would have to double at some point presumably for take-out for East to bid 3NT with the actual hand. East can have at most 2 hearts so he is unlikely to sit. There are at most 15 HCP unaccounted for. Tell me how West is supposed to know that East will have the majority of the remaining HCP? Why could not South hold 9 HCP and East 6 HCP instead and North could also have one or two HCP more leaving even less for East? What is West supposed to do if East bids 3♣ in response to a double? What is West to do if 3♣ gets doubled ? Rainer Herrmann
  23. I am also a big fan getting into the bidding as soon as possible when every card the opponents hold is on the right side (♠Q, ♣K,♦J) and opponents are therefor unable to establish any long suit of their own. After all it is very tough to overbid these deals particularly when vulnerable Of course I am a bit more cautious when I smell this is not the case and my smell is excellent when I can see the complete deal. Rainer Herrmann
  24. What we are discussing here is what to rebid with an unbalanced hand if all of the following conditions are met: 1) our singleton is in partners major suggesting a misfit (this is the most important one. 1NT may well be our last make-able contract) 2) we are in range for a 1NT rebid, for strong notrump players an opening hand with minimum HCP. 3) we have minimum length for bidding or rebidding a minor at the two level (sometimes missing a fit in hearts that way, we would not if we rebid 1NT. After all responder can also be unbalanced!) Phrasing the question like this, and this is the choice we are facing, makes it much less clear what the "worse error" is. Differentiating balanced from unbalanced hands is going to be important if and only if you find a playable trump fit superior to notrump and you do not get too high. Otherwise it only helps the defense against you. Rainer Herrmann
  25. I believe bidding 1NT with a singleton spade is sensible and I do it extensively. However, I do not do the same over 1m-1♥. For once there is a bid between 1♥-1NT and the number of distributions, which have no good other bid, are much fewer compared to a 1♠ response. I rebid 1♠ with 3=1=4=5 and found this quite satisfactory alleviating any need to ever open this with 1♦. Of course you need to alert this and partner needs to be aware of this. If partner is weak he will raise with 4 cards, usually a better contract than 1NT. If partner is invitational we use XYZ and partner bids 2♣. If partner has a game force he continues with 2♦. Over both there are plenty of bids for opener to show less than 4 spades. But this approach also works without XYZ if you use fourth suit forcing as invitational or better instead. Opponents are not likely to interfere once both have passed at least once already. In case they do, responder will assume opener has 4 spades, because the scenario with 3 cards in spades is very rare. Simple and effective. Rainer Herrmann
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