effervesce

3♦ - 5♦?

With a random partner, sure, X for the first. But me and my partner know we often overcall 4 card suits-he'll take that into account.

Without discussion, double of 1 lvl bids should show the usual classic takeout double shapes of 4414/4405/4423 short in their suit unless the hand has extra values. I overcall 1H on the first hand, and 1S on the second. I dont like the fact that they're only 4 card suits vul but its MPs and you do not want partner to make a wrong lead.

You're right. Didnt think of that line :ph34r:

Um... lose to the K, J diamonds is setting trick?

Playing for anything else, like endplaying east seems a less likely line to work.

2H? Making a reverse on a 15 count without a known fit? The aces and kings are nice but it seems too much of an overbid imo.

Wouldnt more different hands be easier to bid/distinguish? Make 1C as 12-16 without a major or 17+ with. Make 1D/1H as 8-11 4+H/4+S respectively or 17+ club/diamond hands.

Looks like 1 spade loser and 1 heart loser if you decide to ruff a spade (just in case the J was a falsecard). To make you need to hold a diamond loser to one - lead a small diamond from dummy? If king diamonds is onside you still make, while making it difficult for east to duck with Kx.

All options look pretty ew to me - 2D rebid seems the smallest lie.

3D most likely. 2D is a underbid at favorable vul. Sure it's only 6 cards, but it is a nice suit with good pips.

3rd seat, partner passed hand, I would not mind 4S. Unlikely to be what the rest of the field bids though. 1S at IMPs, 4S at MPs?

Hope for a squeeze on east? If east holds 4 clubs and 4 spades declarer is home. Win Q diamond, ruff diamond, cash top heart, cash ace club, cash AK hearts, pitching club, exit heart pitching another club, (east has to pitch a club here to keep 4 spades), say west leads a diamond, pitch club and ruff in hand and on the lead of the diamond east is squeezed. Alternatively if west leads a spade win in hand cash the trump squeezing east.

Depends on who you're playing with. I would convert to 5C, but I wouldnt be surprised if partner simply had a hand too good for a simple 4H overcall.

I second TimG's suggestion - however, the book is actually online for free (with permission from the authors).Partnership bidding at bridge (though it's still worth getting a hard copy imo). I highly recommend reading it; it has great stuff on partnership bidding, preemptive bidding and competitive bidding. There are 4 aspects used when defining ODR: a) your hcp strength Now hcp is not the most important factor, but is still important in the ODR ratio. The ODR is defined by the offensiveness/defensiveness. A hand with no hcp can have no defensive strength at all, while in general both offense and defense increase with increasing hcp Their example is this (given opps bidding spades): 8 9753 642 97653 and 8 A753 A42 QT653 the second hand here obviously has a smaller ODR ratio. b ) shape shortage in the opponent's suits are useful offensively, and the more distributional the higher the ODR c) distribution of values values in your and partner's suits are useful offensively, those in the opps defensively d) type of values in your suits, Qs and Js are offensive cards. In the opps suits they are defensive. Aces are neutral in that they can be useful both offensively and defensively. Thus your example hand has a moderate ODR; it is good offense, but the aces contribute equally as well in defense.

And it is kinda stupid to try to quantify the effect of opening 1nt on different ranges the way it is done here. you have no information about the quality of the players, you have no information about the rest of their system. When you make a decision to switch from 16-18, to, say, 10-12, just because of this study, you may gain close to an imp every time you open 1nt, but is it really worth it if the rest of your system losers a third an imp per deal? i feel like i'm repeating myself. Yes, I get your point, you get mine. As for your point about the rest of the system losing out-yes that may be true in a standard system, but some systems (eg strong club) actually have it the other way around, benefiting from the opening of a 10-12 NT - a synergistic effect on the rest of the system whereby using such a range means that other openings are more clarified. For example, putting all 1st/2nd seat 10-12 5M332 in 1NT means that 1H/1S are either unbalanced or maximum in a precision context. It makes inviting opener's 1M much less risky if opener is unbalanced or maximum than either unbalanced and minimum flat. It also allows a 3rd eat preempter more freedom to open 1M, or make a 3x/4x preempt given the reduced chance of game/slams respectively.

Looks like the honors are positioned well over declarer's and spades arent splitting - why present declarer with a contract destiny had foreordained for him to lose. A safe diamond looks best-it is least likely they have a diamond loser/guess.

The OP hand for clarity Qxx=Axx=AQxx=xxx If you expect your passed hand pard to have such a perfect fitting hand as your example whenever you hold the OP hand, you are not playing odds on Bridge. ...and let Us note that your Opponents on this board you have constructed have a double fit in the Pointeds and a profitable "4 over 4" at any vulnerability. So, the =real= question is: if you open this, how often do you think you and your pard will make the correct X, pass, or bid 5 over 4 decision? You better be right considerablt more than 50% of the time, or you will have a difficult time getting and keeping teammates. Then it simply becomes a matter of yours and your opponent's competitive judgement. If you and partner have terrible competitive judgement/agreements, then sure of course opening a hand would be more likely a loss. Such a concern, however, doesnt contribute to whether or not it is correct to open the bidding. Assume all players are good at competitive bidding such that the par spot is reached. I believe opening this as 1D is a long-term winner. Sure, you and your partner may have such bad judgement that making any bid at all will make you lose, and that it would be best for you to take any chance to passout a hand to not lose on that board. That does not change the fact on whether or not it is technically correct to open a hand or not. A more relevant question is, is it more likely you and your partner own the partial, or the opponents. A simulation could probably be run to see which pair is more likely to 'own the hand'.

okay... and what about the loss from defending 2M and either not setting it or setting it not enough when you open 1m instead of 1nt? That was one of the reasons I suggested earlier for the lower gains for opening 14-16 or 13-15. You have less of the 'dont overcall this' scare-factor for a 14-16 or 13-15 opening as compared to a strong no-trump. Maybe the gain in 10-12 1NT is 'I cant overcall this without constructive values'. I dont know there are lots of variables to consider. Anyway, your point about the loss of opening 1m due to opps playing 2M is not as relevant to this study-its about the gain from making a 1NT opening bid. Yes, these gains may be offset elsewhere. What we are trying to work out here is WHY certain point ranges have a greater +IMP/board score when opened than others. In any case, for any range, there will be different hands that the opps can make an overcall on when you open 1m. It'd be hard to compare and quantify such results.

I am also not really sure how valid it is to extract the NT range from the context of the remainder of the system. 1nt 10-12 on hands where you get to open it might well gain you half an imp a board, but on deals where you have to use a different sequence to show the balanced point counts that others open 1nt on, you might be losing that same half an imp a board, or some such. I meant that the gain comes from playing a contract of 1NT, as opposed to 3NT. An opening bid of a 10-12 1NT is more likely to play in 1NT as opposed to 3NT. An opening bid of 16-18 is less likely to play in 1NT as opposed to 3NT. This explanation, whereby the increased likelyhood of playing in 1NT as opposed to 3NT when the point range is reduced, may explain the negative correlation between 1NT strength and IMP/board gain. For example, an opening bid of 10-12 NT (just a number for example) may have a 50% chance of playing in 1NT, and a 15% chance of playing in 3NT. An opening bid of 16-18 1NT may have a 50% chance of playing in 3NT, and 15% chance of 1NT. If, whenever you play in 1NT the gain is 1 imp, and the gain in 3NT is -0.5 IMP, then we see an advantage of opening a 10-12 1NT as 0.5x1 - 0.15x0.5 = 0.425 imp average every time it is opened, while for the 16-18 1NT would be 0.5x-0.5 + 0.15x1 = 0.1 imp every time a 16-18 1NT is opened.

It doesn't even explain that...how many of the best players play a 16-18 NT? How does their quality of play compare to those who play 15-17? I also don't think it's fair to compare all seats equally. People who play a 10-12 1st and 2nd and 15-17 3rd and 4th may have an advantage because their partners are more restricted than playing 16-18 or 15-17 in all seats. That raises an interesting point - perhaps another advantage of the 1NT 10-12 opening is the probability of playing in 1NT. As 1NT is probably THE MOST DIFFICULT contract to defend against, the gain for the 10-12 1NT could be due to 'declarer advantage'. This advantage is probably much smaller in a contract of 3NT, which is probably easier to defend than 1NT.

Open 1D. Wtp? There are still hands in which game is stone cold, for example opposite Kx KQxxx Kxx xx unless you open such hands 1M in 1st/2nd. I think probability-wise you and partner have better chances for a positive partial score than the opps; however even if you and the opps have similar probabilities of partial scores, the odds are tilted due to you and partner having chances for game and the opps close to zip.

hmm... i obviously failed reading comprehension... does this explain why 15-17 is such a big winner? No it does not - it only explains why more and more people are turning from 16-18 to 15-17 - that the disadvantage of the 1x-1NT rebid being 12-15 outweighs the benefit of a precisely 19 pt 1x-2NT rebid in a 16-18 pt range. However, this does NOT explain why an opening bid of 15-17 1NT performs better than 16-18.

Precision is my precious. I've also tried magic diamond; seems to work decently but I dont like the 1C/1D continuations.

i find it curious that there is a peak at the 15-17 range. there's a clear trend in increasing imps from the higher ranges to the lower ranges otherwise. any idea why? I dont know, maybe its that the weaker 'strong NT' preempts the opps more effectively when it is opened compared to 'weak NT', and thus they're still as scared to overcall a 15-17NT just like a 16-18 as it is still a 'strong NT'? Whereas for 14-16 people tend to overcall more, treating it more often as a 'weak NT'? I'd also wonder about the effect of 'variable NT' openings- if people open one range in 1st/2nd or 3rd/4th, or one range vul and another non-vul, that perhaps may have influenced the IMP gain. 10-12 tends to be opened in 1st/2nd seat - perhaps the preemptive value is greatest in such seats, while retaining constructive bidding with partner. Such 'seat effects' may perhaps be why 14-16 and 13-15 seem less effective. This idea is supported by the fact that the 10-12 NT is the ONLY range that gains IMPs when opening light - it appears that the main gain of 10-12 NT is its preemptive effect, which more than counterbalances the loss in constructive bidding. Other NT ranges lose more in opening light from constructive bidding than gain in preemptive bidding.