Thursday, December 18, 2014

Doubling 3NT for a lead (part two)

Last time, we talked about the general subject of doubling 3NT for a lead. Now, let's talk about the most problematic of all calls: double after it goes 1NT pass 3NT. You could play that partner could lead any bad suit, but it won't be any surprise when both defenders are weak in a minor suit on this auction. So, to me it makes sense to restrict leader's choice to a major. Some pairs play that double asks for the lead of a specific major. But unless you play a lot with this particular partner, it will rarely come up.

So, what sort of suit do we need for the double to work? How about ♠AKQxx? At the recent NABC in Providence, RI, this exact situation came up in a match against Benito Garozzo on my right and Jan van Cleeff on my left. Was my suit good enough to double with? I didn't have forever to think about it (lest I pass UI to partner) so I had to make up my mind quickly. Yes, I decided. There followed several tortuous minutes while I waited for my opponents to consider their options and for my partner to lead (this last didn't take long). Benito redoubled to ask how opener's majors were and opener passed to say "pretty good." However, none of this was clear to me at the time. It appeared to me that they didn't have a clear system for this situation (I knew who RHO was of course, but not LHO). My partner, Vincent, put his card face down. "Turn it over", I said. The deuce of spades. Hallelujah! Dummy came down with two small spades and declarer asked a fatuous "what are your leads?", and played the ten at trick under my queen. This card, incidentally, caused quite an upset—to say the least—for the 87-year-old Garozzo. But it was all play acting by van Cleeff and my feeling of victory was very short-lived. Declarer started with JTxxx of spades and wrapped up 10 tricks to go +1400. We lost 13 IMPs on that deal.

Was my bid so very bad? or was I just a little bit unlucky? I determined to find out. This wasn't a trivial problem in probabilities and I had to write some Java code to figure it out. But now the results are in!

I set up the following conditions: LHO has at least two cards in every suit and RHO is nominally balanced (so at least one spade). For the five remaining spades, LHO has 5 vacant places, partner 13 and RHO 12. Additionally, LHO has fewer than six spades; RHO has fewer than five (no transfer) and, 80% of the time, fewer than four (he didn't use Stayman). I also adjusted for the case where partner has four or more spades, because he might not recognize that spades is our suit. With five I assumed, he will not lead spades and with four I assumed he will pick a spade half the time. Probability of success? 52%.

That's really not enough (as I discovered) to make the bid worth while. Let's see what we get as an expectation of IMP gain.

We assume that when we are successful, running our suit, they will run to a minor-suit half of the time (bidding game half of those times and making it half of those times); otherwise they will sit for the double. When we are destined to fail, we assume that they will redouble, as Garozzo did. We also assume for the sake of argument that they are vulnerable.

In the case of my AKQxx, we have the following outcomes (with probabilities and expectations of IMPs):

Bad game6.5%+12+0.78

Oh dear! Overall, the expected gain is negative! With so many possible things to go wrong, not to mention the fact that partner might happen on a spade lead all on his own, it's a bad idea to double. There's also the psychological factor to take into account when playing with humans rather than robots. Partner (not to mention doubler) may be so disheartened by this result that the rest of the set suffers. I don't think that happened in our case (although we netted minus 3 on the other six boards), but it easily might.

Let's take a look at some other cases:

HoldingP(success)Expectation of IMPs

The two middle situations are much better. Having the jack in the second case makes quite a big difference mainly because it increases the probability of success, but also because it prevents a redoubled overtrick. AKQTx would be better than my hand but obviously not as good as AKQJx. Adding a sixth card increases the probability of success and also the penalty when they sit. Note that AKxxxxx just isn't good enough. Basically, you have to catch partner with two and even then you need an even split. Having the jack would help in those cases where opener has a doubleton queen or dummy (or partner) has her. But even then, you're gambling quite a bit.

What about a topless solid suit such as KQJxxx with an outside ace? The overall probabilities and expectations are approximately the same as when you have AKQxxx. However, you will have to face the rather likely possibility that opener has 8 running tricks in addition to the ace of your suit.

There's another way this can backfire, as my partner and I learned a number of years ago at a sectional Swiss in Maine. Our non-vulnerable opponents were playing a weak no trump and the auction went 1NT—3NT.  I doubled with something like ♠xxxx KQJxxx x ♣Ax. Partner had something like ♠xx Ax in the majors and quite reasonably assumed my suit was spades. We learned then, due to an adverse swing of 12 IMPs, that it might be a good idea to cash a major suit ace first just to see partner's card.

So, here are my conclusions if you're thinking of doubling 1NT—3NT for a major suit lead (assuming you've discussed this situation with partner):

HoldingTo double or not to double?
AKxxxxxAbsolutely not!
KQJxxxMaybe but be ready to apologize

Monday, December 15, 2014

Doubling 3NT for a lead

I've previously talked about various different sorts of lead-directing double. But I couldn't find any article where I had discussed doubling a 3NT contract for a lead. It's uncommon, for sure, but when it comes up, you really need to be on the same page with your partner.

Following the same principle of the Lightner double of slams, there is little reason to double a freely bid 3NT to increase the penalty. The arithmetic just doesn't support it. Suppose that they have bid a silly 3NT, not vulnerable, and you think, based on the auction and your holding in the suits bid on your right, that the contract will go down on partner's normal lead, most hopefully by two tricks. Let's say, for the sake of argument, that the probabilities of various numbers of tricks for declarer are for 6 thru 10: 10%, 40%, 30%, 15%, 5%. At the other table, your teammates are in the more sensible contract of 2NT. The lead and the number of tricks taken are the same at both tables (yes, I know this is a big assumption). The number of IMPs in your favor is expected to be: 9 * 10% + 6 * 40% + 6 * 30% + -9 * 15% + -9 * 5%, which comes to 3.3. This is modestly positive but it might actually go negative if the opponents redouble when they are making, especially if they are vulnerable. And, then there's the very likely eventuality that they will run to a making part-score or, worse, game. And, far worse, the ignominious possibility that your double will tip declarer off to the winning line!

Contrast this with the situation where the opponents are actually going to make (-6 IMPs) on partner's normal lead, but will go down when you tell partner what to lead (+5 IMPs). That's a swing of 11 IMPs. The swing when the opponents are vulnerable would be 16 IMPs.

Unfortunately, you can't lean over to partner and say "lead a club", though you could try coughing (JK). You have to have a general agreement about what lead you want based on the auction.

Here's the scheme that I think makes the most sense and is easiest to remember:
  1. if leader has bid a suit, then lead that suit
  2. else if doubler has bid a suit, then don't lead that suit
  3. else if dummy has bid a suitthen lead that suit
  4. else use your judgment, normally leading your lesser major suit.
I'm also willing to play #2 as "do lead my suit" but it seems to me that partner is probably going to lead my suit anyway. The idea of "don't lead my suit" comes from George Rosenkranz's Tips for Tops. It can often happen that either because doubler had no opportunity to bid two suits or simply because, say, he opened a suit with nothing much in it he thinks that they will go down if you lead something intelligent. It might well be dummy's first bid suit. Let's say that the auction has gone 1♠ (X) p (2) p (3NT) p p X all pass. Your hand is ♠Kx Jx Txxx ♣Jxxxx. Normally you would lead the ♠K. But partner is asking you not to lead a spade. What could his other suit be? Could it be hearts? Double of dummy's 2 call would have been takeout-oriented, not penalty. Declarer has the spades stopped and he has enough tricks in one or both of the minors for his contract. He's relying (inadvisably) on dummy's hearts and/or hoping you will lead a spade. Get that J on the table, therefore.

The reason for the first rule is that partner may be loath to lead away from a holding such as AQT73 after his RHO has bid notrump. But sometimes players will consider J982 a stopper. If partner has the K doubleton, you can take the first five tricks. But if you lead something else, looking for partner's entry, by the time you get to run those spades it may be too late. Of course, you might have been going to lead your suit anyway, lose the first trick to declarer and then wait for partner to get in and lead through. But there are two things that can go wrong with this plan: declarer may be able to hold up long enough to exhaust partner, or partner may have nothing to get in with. This is particularly true when you have opened the bidding or overcalled—the very occasions when partner will want to take the opportunity to tell you the good news.

In any case, this worked out well during the recent 0-5000 Blue Ribbons in Providence, RI. I opened 2D (weak two) with nobody vulnerable. My diamonds were QJTxxx and I had an ace on the side, I think (ACBL "Live" has lost the details of this event already so I can no longer be sure of the whole layout). My RHO ended up in 3NT and partner doubled with Kx. We soon had a top with +500.

In the second part of this blog, we will talk about the most problematic of all calls: double after it goes 1NT pass 3NT.

Sunday, December 7, 2014

The principle of substantive discretionary bids

I mentioned this idea long ago in one of my first blogs in this series (see Every bid tells a story) and maybe it's time to dust it off and give it another airing. For brevity, I prefer to call it the "Principle of Stuff."

It strikes me as simply common sense that if you are making discretionary bids (that's to say a free bid when an opponent was the last to act, especially when it was your right-hand-opponent who last acted) then you should have some substance in your suit. And I will go further. The more you are sticking your neck out, the better your suit will be for the purposes of partner's lead.

Here's an example that came up in a club duplicate. I dealt myself the following hand at favorable vulnerability: ♠AJ T98642 AKQ7 ♣4. Naturally, I opened 1 which was followed by 2♣ on my left. Partner passed smoothly, as did RHO and it was back to me. I didn't have to bid again, although with a 14 count and shortness in their suit I think I always would. But technically my second bid was discretionary. So should I repeat the bad six-bagger, or bid diamonds where I actually had some stuff and would welcome a lead if the opponents win the auction with 3♣? Double is also a possibility I suppose but with only two spades and no extras to bid a third time, that seemed unpalatable.

This decision (2) helped us to a 75% board and I later mentioned to my partner that I had chosen to bid diamonds at my second turn at least partly for lead-directing purposes. He was a little surprised, saying that if he'd ended up on lead, he would have certainly led a heart. So much for this idea being "common sense."

When you are bidding in a constructive (non-competitive) auction, your choice of bids is largely dictated by your system and the relative lengths of your suits. With two five-card suits, for example, you will open the higher ranking and at your next turn bid the lower ranking. There's no way for partner to infer which might be the stronger suit. But this is because you believe that it's your hand and that you are simply trying to determine what strain and what level to play in.

If, instead, you make an overcall you are putting yourself in some danger. Partner may have no fit and no high cards. You should have some good stuff in your suit. What if your hand is good enough to make two overcalls without any encouragement from partner? Having survived your first overcall unscathed, you are seriously sticking your neck out the second time. Partner can of course give preference to the first suit if he likes it more, but there may be no escape from a bad result if partner has little support for either suit. It makes sense then that the second suit is likely to be the better suit because if it was weak, you would be unlikely to mention it at all – you haven't been forced to make a second overcall. Perhaps it's only a minor inference but it seems to me to be valid.

Here's a more compelling example from the recent 0-5000 Blue Ribbons...

What's going on here? Partner could have bid 2NT over 2♠ to show both minors, right [well, let's assume so, anyway]. Why is he bidding out his suits like this? He's either a lunatic or he's get a good hand with both minors. Which do you think is his better minor? If he had equal quality in both suits, he might perhaps have bid 2NT. But what we do know for sure is that his clubs must be very good to stick his neck out quite so far (a four-level solo effort, vulnerable).

So, are you tempted to do anything? 5? What makes you think we can make 5? The spade king might be useful but the hearts are tram tickets. We have no fitting honors in diamonds. Partner might be able to make a four-level contract with a trick or two from our side. But we basically have half a trick unless he has losing clubs to ruff. And if 5 might be a sacrifice, why are we doing it red on white?

How about double? Partner has overcalled two suits, so double will not be cooperative. It will be penalty. Do you think they can make 4♠? Each player is limited in values. North seems to have an extra spade. But I see no reason to assume that they can actually make 4♠. Indeed, our singleton is opposite partner's best suit. That sounds like a bit of a misfit. Double is the right call (+300 for about a 90% board) but pass would be acceptable too (70%).

On defense, I think it's rather obvious that we will be leading a club and indeed that is the only lead to achieve down two. Here is the hand record. Possibly, West overbid in the circumstances, but it gave our side the chance for a very good score. Without the club bid, the opponents would most likely be making 140 for about 40%.

So, I think it's worth paying close attention to the way partner bids his suits, especially if there was an alternative method of showing both suits. A dangerous bid should be based on a good suit. Therefore, when my partner freely bids a second suit, I always lead it if there's no clear reason to lead the other, such as a singleton. It seems to work out pretty well most of the time.