respond to double

[mgoetze]

Do you expect west to sit for 1♣X in the layout above?

Do you expect West to bid 1♠, just to discover that East actually has 4 clubs and only a singleton spade?

[Antrax]

There's no need to psychoanalyze me, at least until you see a hint of dishonesty in my questions. When I thought about the hand I figured "if he has the short club, he'll run away from 1♣ doubled, and if he has club length and strength he'll sit for it, and either way you get the worse of it". That's the point I'm trying to make, mainly to learn from others correcting me. So far I see disagreement (probably from experience), but it's difficult to say I can infer the principle from this. Is the 4-3-3-3 hand opposite a 0-HCP dummy the one they're more likely to have than my layout?

I read somewhere that even when playing 5CM, usually a 1♣ opener has a 4+ card suit. Is that incorrect?

[gwnn]

Antrax, like I said above but maybe not clearly enough, if I kibitz your table, seeing none of the hands and I see that you opened 1♣, there's almost 50% chance that you have 3 or 4 clubs. Now imagine you opened 1♣ and I see your RHO who has 5 clubs! Obviously the 50% chance that you have 3-4 clubs have gone up a lot, maybe to 80%. Someone would need to make a simulation on this, but do you see my point?

 

The thread with the exact numbers is here:

http://www.bridgebase.com/forums/topic/47378-probability-question/

 

The estimates for 3-4 clubs are somewhere between 40 and 50% for all estimates.

[Antrax]

I'm not sure which way to lean, intuitively. You see long clubs and you see your partner has short clubs, don't the two balance each other out in some way?

[gwnn]

Partner's takeout double does make LHO slightly longer but they hardly balance each other out. Partner doesn't promise 0-1 clubs with his double, he could have 2, he is unlikely to, but could. Meanwhile we know for a fact that we have 5 clubs and we know that declarer often has 3-4 clubs. Well, this is just my intuition speaking and I would be presumptuous to say that my intuition is inherently better than your intuition. It would be nice if someone could make a bunch of simulations.

[aguahombre]

The passers, whether we agree with pass or not, need not be concerned with the odds on how many clubs opener has; and whether opener will remove his own opening is not something of concern either, yet.

 

The passers feel that whatever happens, they will be enroute to at least as good, if not better final result than if they had bid. I don't pass, and would bid 1D. But I surely can see how that decision could miss out on a bigger penalty.

[mikeh]

Let me add to gwnn's observations about the likely club layout. If partner has a minimum type of takeout double, which is the main case causing us concern about defending, then he probably has no more than 4 spades. This, in turn, suggests that opener will usually (not always, by any means) have some spade length. The same is true, to a lesser degree, about hearts....it is unlikely, tho possible, that opener has fewer than 2 hearts and fewer than 3 spades.

 

This means that the a priori odds of opener holding long(ish) clubs are somewhat reduced.

 

Indeed, my main concern about defending is not when partner has a minimum takeout double...my concern is that he has a powerful one-suiter, possession of which negates the inferences I draw about opener's club length. Now there is a risk of 500 against 600 or 620, in addition to the risk of their making.

 

But partners tend to hold semi-balanced takeout doubles of all strength ranges more often than they hold single-suit monsters.

[mikeh]

Partner's takeout double does make LHO slightly longer but they hardly balance each other out. Partner doesn't promise 0-1 clubs with his double, he could have 2, he is unlikely to, but could. Meanwhile we know for a fact that we have 5 clubs and we know that declarer often has 3-4 clubs. Well, this is just my intuition speaking and I would be presumptuous to say that my intuition is inherently better than your intuition. It would be nice if someone could make a bunch of simulations.

Haven't we seen several posts in which strong players (and others) advocated takeout doubles on 4=3=3=3 or 3=4=3=3 shape with, say, 14 hcp, on the basis that it is better to double and go quiet than to pass and have to contemplate backing in or getting shut out?

 

We all double, and think it routine, on AJxx AQx Axx xxx, don't we? And a 4=4=3=2 is a another routine double. So while I am not choosing my pass on the basis that partner 'rates' to have xx or better in clubs, I certainly won't pull based on his 'rating' to have a stiff.

Btw, if it is a stiff, why can't it be the 9, or why can't dummy hold the 9? After all, if we give lho AKxxx, the odds are 50-50 that the 9 is in either partner's hand or in dummy.

[ggwhiz]

I agree with Mike in that the upside to pass is HUGE especially if only down 1 on a partscore hand.

 

With me leading hearts through the opening bidder (and the ♠Q) we don't need a bunch of trump tricks and may have them.

 

Also, if they pull to something that we decide not to double a 1nt bid by me now describes this hand nicely, better than a direct 1nt which could be much flatter with much shorter/weaker clubs.

 

Partner will not fear notrump as an option after we pass and if we have game, 3nt is the only one that looks likely to me.

 

A 1♦ bid could be made on xxx, xxx, xxx, xxxx in the extreme and is much too conservative at matchpoints when you MAY have them by the throat.

[karlson]

Do you expect West to bid 1♠, just to discover that East actually has 4 clubs and only a singleton spade?

 

Don't you think this is quite unlikely when the opponents have passed 1♣X?

[Antrax]

Well, this is quite interesting. I hope I didn't hijack your thread, derq.

[JLOGIC]

Do you expect West to bid 1♠, just to discover that East actually has 4 clubs and only a singleton spade?

 

Sitting for 1C X with AKx would be absolutely horrible. Sitting for 1C X p on 1C X p p is almost always going to be wrong, but with only 3 of them it is really crazy!

[mikeh]

Sitting for 1C X with AKx would be absolutely horrible. Sitting for 1C X p on 1C X p p is almost always going to be wrong, but with only 3 of them it is really crazy!

I agree with this: but if he has only 3 ♣s, then he is 4=3=3=3/3=4=3=3/4=4=2=3 and (presumably) less than a strong 1N, so where is he going to go, with any success?

 

(ok, he MIGHT be on 18-19, if partner is on a minimum, but we can't base our bidding on that as a strong possibiity, and even then, passing may well be right....we double the runout to 1N and a club lead may carve it up)

 

And, of course, when he is on a 3 bagger, the odds are that his partner will hold 3 or even 4. Imagine responder with 3=3=3=4 and opener with 4=3=3=3 (doubler 5=4=3=1 big). Go ahead....make my partner's day by playing 1♠ :D

 

While pass comes with no guarantees, it offers a huge upside with sufficient frequency that imo it is the call at any form of scoring.

[JLOGIC]

Yeah I would pass, I was just arguing with the point that LHO should not run with a hand like that.

 

I am not optimistic about defending 1S X either if partner chooses to double. Partner will double 1S in my book with a holding as weak as KTxx. In fact, 655321 said he would not even sit for 1S X.

 

That is a debatable view, but also not a reason to not pass 1C X.

 

My first priority is "I'll be happy defending 1C X" if they opps can/will/should run and if that will or will not be profitable, I have no idea, I'll cross that bridge when I come to it, but I don't think I gain anything by just bidding 1N to begin with.

 

I just wanted to emphasize that one should extremely often run on the auction 1C X p p for the sake of getting it out there since it is an important bridge lesson, regardless of our decision on this hand.

[gwnn]

I did a little simulation but I don't claim it to be super accurate. It gave a priori

 

3 : 19.6%

4 : 29.8%

5+: 50.5%

 

giving us the hand from the OP:

 

3 : 35.6%

4 : 37.7%

5+: 26.6%

 

giving N a t/o double:

3: 31.1%

4: 41.9%

5: 27.0%

 

for a 1C opener I used 12+ hcp, always from 33 in the minors, never from 44, discard 15-17 balanced, discard any 20+, discard 5 card majors

for a t/o double I used 12+ hcp, 3-4 card in both majors, 3-5 cards in diamonds, 0-2 cards in clubs.

 

So yes, the takeout double does make LHO a little longer, but not a lot. And my 80% estimate was off, it is only slightly higher than 70%.

 

edit: the way I like doubling is 2-5 cards in diamonds, any number of clubs (but I do not double with 3-3-2-5 :) ). just out of curiosity I ran the script for these loose doubles too:

 

3 : 42.1%

4 : 39.0%

5+: 18.8%

 

Obviously this case is slightly silly, but the one I used above is slightly too strident.

 

All of these cases I ran for 100k matching hands each.

[manudude03]

Speaking of whether or not opener should run, here's a slightly different auction:

 

From the Australian Bidding Forum Hand Four

 

1D-P-P-X-P-P-?

 

A lot of the discussion was about whether or not opener should have pulled with 4432. It's not the exact same (since responder still has a chance to run), but it does have a lot of parallels with the OP auction.

[Antrax]

Cool. So is the 75% shot at getting a partscore-penalty (200/500) better than your shot of finding game if you bid?

[gwnn]

Antrax, just because declarer has 5 clubs, he is not going to make it automatically. The points will be after him and despite what you might think, dummy will not have a lot of entries to finesse trumps through us so many times.

[Antrax]

I mostly worry about the layout where dummy has some shortness and we can't draw trumps fast enough. Is it really that difficult to get to seven tricks in clubs when you have half the deck and a 5-2 or 5-3 fit, even with clubs breaking badly?

[gwnn]

5-3 fit? :(

 

I don't have the numbers in front of me but dummy had 3 cards something like 5% of the times that his partner had 5 cards. But that's OK, you're trying to make a point...

Edited August 16, 2011 by gwnn

[Antrax]

Okay, so 5-2. 4-4, 4-3. I don't know, I'm just really not sure how easy this is to beat and how likely it is we're missing game. Mike Lawrence advocates you only sit for a doubled low-level contract if you can guarantee drawing declarer's trumps early, and you have sure trump tricks. I'm trying to understand if I understood him wrong, or if people disagree with this view.

[the hog]

Okay, so 5-2. 4-4, 4-3. I don't know, I'm just really not sure how easy this is to beat and how likely it is we're missing game. Mike Lawrence advocates you only sit for a doubled low-level contract if you can guarantee drawing declarer's trumps early, and you have sure trump tricks. I'm trying to understand if I understood him wrong, or if people disagree with this view.

 

You understood him correctly. It seems some disagree with that advice.