mtvesuvius Posted February 18, 2009 Report Share Posted February 18, 2009 Opponents silent, you arrive in a disgusting 6♥ contract after an unspeakable auction... A♣ lead, and a trump switch, and trumps are 2-2, and when you run the Q♠, LHO plays the 6 and RHO the 5. Opponents are playing UDCA, can you trust them to be giving count? [hv=d=n&v=n&n=sa9843hkqj54dk8c8&s=sqj2hat73dat6cqt4]133|200|Scoring: MPOn the A♣ lead, LHO plays the 7♣. 2♥ switch and ♥ are 2-2.[/hv] Drop Kx onside or pin the 10? Quote Link to comment Share on other sites More sharing options...
Carnoustie Posted February 18, 2009 Report Share Posted February 18, 2009 I never trust opps carding in situations like this... And since I see both lowest spots left, someone is falsecarding anyway, or they are 4-1, and then I'm screwed anyhow..I'm never very good in percentages, but isn't this a complete guess? We are either playing for Kx and 10xx, or Kxx and 10x. I would think both layouts have the same chance... *edited* (sorry, missed something, too early, not awake yet) Quote Link to comment Share on other sites More sharing options...
Trumpace Posted February 18, 2009 Report Share Posted February 18, 2009 How about ruffing out one of the minor suits first? You might get some extra information. Quote Link to comment Share on other sites More sharing options...
mtvesuvius Posted February 18, 2009 Author Report Share Posted February 18, 2009 How about ruffing out one of the minor suits first? You might get some extra information. on ♦ LHO plays 3, 4, 7. RHO 2, 5, 9.on ♣ LHO play 2, 5. RHO J, K. Quote Link to comment Share on other sites More sharing options...
Trumpace Posted February 18, 2009 Report Share Posted February 18, 2009 How about ruffing out one of the minor suits first? You might get some extra information. on ♦ LHO plays 3, 4, 7. RHO 2, 5, 9.on ♣ LHO play 2, 5. RHO J, K. I guess I go for the drop then. Quote Link to comment Share on other sites More sharing options...
kfay Posted February 18, 2009 Report Share Posted February 18, 2009 If LHO were looking at Kxx he must duck the first trick to put you to a guess. If LHO has Kx they can either duck or put on the K and you are still 'guessing' the next round (since you must play K from K10) even though pretty much anyone worth their salt will hook RHO for the 10. Looks like a restricted choice situation, right? I pin. This is how I've always thought about this holding. Maybe I'm wrong. Quote Link to comment Share on other sites More sharing options...
jdaming Posted February 18, 2009 Report Share Posted February 18, 2009 I agree with pin as the chances that someone covers with Kx is higher than Kxx also for Kfays reasons I would only trust the signals if they are that newer player type who "just learned signaling" that always signals everything without ever thinking about who wants this info. Quote Link to comment Share on other sites More sharing options...
Lobowolf Posted February 18, 2009 Report Share Posted February 18, 2009 If LHO were looking at Kxx he must duck the first trick to put you to a guess. If LHO has Kx they can either duck or put on the K and you are still 'guessing' the next round (since you must play K from K10) even though pretty much anyone worth their salt will hook RHO for the 10. Looks like a restricted choice situation, right? I pin. This is how I've always thought about this holding. Maybe I'm wrong. ...and the moral of the story is duck with Kx...smoothly!? Quote Link to comment Share on other sites More sharing options...
Fluffy Posted February 19, 2009 Report Share Posted February 19, 2009 What Kevin said. Quote Link to comment Share on other sites More sharing options...
kfay Posted February 19, 2009 Report Share Posted February 19, 2009 If LHO were looking at Kxx he must duck the first trick to put you to a guess. If LHO has Kx they can either duck or put on the K and you are still 'guessing' the next round (since you must play K from K10) even though pretty much anyone worth their salt will hook RHO for the 10. Looks like a restricted choice situation, right? I pin. This is how I've always thought about this holding. Maybe I'm wrong. ...and the moral of the story is duck with Kx...smoothly!? Yeah I was thinking about this position a lot yesterday after reading the thread. I think I've finally concluded after some paperwork that if you know the position you should always always always duck from Kx. Covering to 'protect' KT is a red herring. So theoretically I'm truly at a 50-50 guess if I can pick up the position. However, the position isn't always known and sometimes people will cover the Q from Kx for this very reason. If you can count on a cover some portion of the time then it definitely becomes odds-on to play for the pin. Of course now sometimes you have to figure that they might cover from Kxx for the same reason, but maybe you can assume that this is less frequent. Quote Link to comment Share on other sites More sharing options...
Echognome Posted February 19, 2009 Report Share Posted February 19, 2009 Of course now sometimes you have to figure that they might cover from Kxx for the same reason, but maybe you can assume that this is less frequent. If they cover from Kxx, it's not a problem. The T will pop when you lead from dummy. From KTx, they always have one trick. Quote Link to comment Share on other sites More sharing options...
kfay Posted February 19, 2009 Report Share Posted February 19, 2009 Of course now sometimes you have to figure that they might cover from Kxx for the same reason, but maybe you can assume that this is less frequent. If they cover from Kxx, it's not a problem. The T will pop when you lead from dummy. From KTx, they always have one trick. lol. duh yeah. i knew this but for some reason it just occured to me to say this at the end my post and i didn't censor myself. Quote Link to comment Share on other sites More sharing options...
Trumpace Posted February 19, 2009 Report Share Posted February 19, 2009 I think I've finally concluded after some paperwork that if you know the position you should always always always duck from Kx. If I recall correctly, this is a mixed strategy (or game theory) problem and the answer was to cover with probability 1/3. Perhaps someone can answer for sure. btw, if you have a count, you don't need all this :) It looks like LHO is 2-2-3-6 (yes ♣J and ♣K could be false cards, but if I ruff one club before playing ♠Q... {didn't try to time it out though}) Quote Link to comment Share on other sites More sharing options...
Stephen Tu Posted February 19, 2009 Report Share Posted February 19, 2009 If I recall correctly, this is a mixed strategy (or game theory) problem and the answer was to cover with probability 1/3. Perhaps someone can answer for sure. No. The answer is defender should never cover. Actually against an optimal declarer anything from cover never to cover 1/3 is equivalent. Everything within this range is the same, as declarer should play for the pin if not covered, and play defender for KT doubleton if there is a cover. So Kx always takes 2 tricks whether you cover or not. Now, if you cover > 1/3, then declarer should switch to running the 9 if covered, losing to KT doubleton but getting it back and then some when you cover. However, against a non-optimal declarer who thinks you are a bad defender & cover more than you do, and always hooks on the way back, you maximize your gain by never covering. Of course, the issue is that declarer might not have the QJx depending on the bidding. Letting declarer succeed with the Chinese finesse with Qx might be catastrophic. That complicates matters greatly. Quote Link to comment Share on other sites More sharing options...
Fluffy Posted February 20, 2009 Report Share Posted February 20, 2009 haven't you though of what hapens when we lead ♠Q from ♠Q10xx? Ducking ♠K smothly is not very succesful. Quote Link to comment Share on other sites More sharing options...
Hanoi5 Posted February 20, 2009 Report Share Posted February 20, 2009 Play the Queen and see what happens. If it isn't covered I go for the pin (which looks always better), if it is covered I have to decide whether to run the nine or drop the 10 and... that's another topic. Quote Link to comment Share on other sites More sharing options...
dicklont Posted February 20, 2009 Report Share Posted February 20, 2009 Pin the 10. Left has Kx or Kxx. Right has 10x or 10xx.No need to think about K10xx or K10x on our left, we lose against that anyway. With Kxx covering gives away the suit.With Kx west could have covered to make us believe he holds K10.So I play for 'best' defense and pin 10. Quote Link to comment Share on other sites More sharing options...
kfay Posted February 20, 2009 Report Share Posted February 20, 2009 If I recall correctly, this is a mixed strategy (or game theory) problem and the answer was to cover with probability 1/3. Perhaps someone can answer for sure. No. The answer is defender should never cover. Actually against an optimal declarer anything from cover never to cover 1/3 is equivalent. Everything within this range is the same, as declarer should play for the pin if not covered, and play defender for KT doubleton if there is a cover. Is this true? Is that because stiff K is less likely than KT? I guess that kind of makes sense... I would always hook on the way back though, since you can also cover from Kx. Quote Link to comment Share on other sites More sharing options...
rogerclee Posted February 20, 2009 Report Share Posted February 20, 2009 I just want to throw out there that in practice, I would just play for the pin and don't think it's that close. For some reason, it is much more common for LHO here to duck with Kxx than Kx. I don't know if I think this because in general there are more Kxx's than Kx's though. Quote Link to comment Share on other sites More sharing options...
Stephen Tu Posted February 20, 2009 Report Share Posted February 20, 2009 Is this true? Is that because stiff K is less likely than KT? You can't do anything about stiff K, you always lose a trick to the T eventually even if you hook on the way back. If LHO covers you are only comparing KT doubleton vs. Kx. I guess that kind of makes sense... I would always hook on the way back though, since you can also cover from Kx But that depends on how often the opponent is covering from Kx. If he is in fact never covering, you are losing to all the Kx's and KT doubleton. It would be better to at least pick up KT doubleton. If he is covering say half the time (> 1/3), then hooking on the way back will show a profit. Playing for KT doubleton is the unexploitable line. Playing for Kx is exploiting someone who covers too much, but you are losing extra times if you are wrong about them. It probably is the right play against an average unknown opponent though, especially when the QJx is concealed and could be some other holding where covering is a necessity. It's much easier to duck when the QJx is in dummy, although I think weak opps will still tend to cover too much. Quote Link to comment Share on other sites More sharing options...
maggieb Posted February 20, 2009 Report Share Posted February 20, 2009 I just want to throw out there that in practice, I would just play for the pin and don't think it's that close. For some reason, it is much more common for LHO here to duck with Kxx than Kx. I don't know if I think this because in general there are more Kxx's than Kx's though.I don't think that there are more Kxx's than Kx's, I think there are an equal number, is that correct? I'm getting a little confused here, since we should subtract the K10x and K10 holdings. It just seems to me that the nuumber of Kx holdings with LHO is equal to the number of 10x holdings with RHO, is that a good way to think about this? I do agree with you that for psychological reasons it is better to play for the pin, and fortunately (as others have pointed out) it is also correct for technical reasons. So I'm pinning as well. I think that Stephen Tu is right that if LHO covers your queen, then you should play for K10 against good opponents who know to duck with Kx, but against most opponents it is probably better to finesse since so many cover an honor with an honor. Also, against most opponents, if they have to think about it then they don't have K10. :) Kfay, stiff king doesn't matter I think because you can't pick up 10xxx anymore. Quote Link to comment Share on other sites More sharing options...
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