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Choose your poison

#1 User is online   Cyberyeti 

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Posted 2021-May-09, 03:53



Once you make your choice the N hand is in the spoiler and you can decide what you want to do with that over your choice.

Spoiler


This was dealt while practicing so no particular form of scoring but feel free to say if you'd do different things depending on that
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#2 User is offline   DavidKok 

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Posted 2021-May-09, 04:15

Double, intending to pull 5 to 5. This traditionally shows a 'big diamond hand', and if partner raises to six with middling values I'll have to live with that (and who knows, two black aces and two small diamonds and it might make).

If partner bids 4 instead I'm passing. I don't love it, but that's preempts for you.
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#3 User is offline   LBengtsson 

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Posted 2021-May-09, 04:22

I chose X, looked at spoiler and thought north hand could be east hand :)

now having looked I would still X. you can run to 5. occasionally you will go for -800/1100 however that should not change your decision. bidding 5 direct over south 4 can miss fit.

btw what does north bid over west X? east/west can easily miss a slam if they decide to penalise you, possibly in 5X
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#4 User is offline   TMorris 

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Posted 2021-May-09, 04:56

Double seem right to me. Trying to be perfect after a pre-empt is pointless. I will pull 5C to 5D and live with the consequences
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#5 User is offline   nige1 

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Posted 2021-May-09, 05:16

CyberYeti's poison West
+++++++++++++++++++++
I rank:
1. Double = keep in the picture,
2. 5 = a poor second choice.
Spoiler

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#6 User is offline   Winstonm 

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Posted 2021-May-09, 09:39

I think you really are pretty much compelled to double but I certainly hope partner can bid and won't pass with a balanced smattering of cards.
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#7 User is offline   Douglas43 

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Posted 2021-May-09, 10:28

At IMPs I'd prefer to bid 5 because a 4-4 Spade fit might run into trouble.

At matchpoints, the extra points for the major might tempt me to double and hope for the best.
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#8 User is offline   gszes 

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Posted 2021-May-09, 14:30

With so little needed (from partner)to make game Axxxx xx T8 xxxx I feel compelled to try x. I was curious to see what the spoiler was going to bring.
After 4h x and with the opps having a 9/10+ card diamond fit AND heart shortness I feel playing around looking for a penalty just seems wrong. I intend to bid slam even if partner were to show me no key cards so I might as well try for 7 just in case partner has the heart AK. I am indeed willing to gamble p does not have a side ace vs the heart ace.

4n rkc fortunately I do not play or recommend those void showing variants since the information is rarely useful and it can backfire sometimes getting us too high.
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#9 User is online   Cyberyeti 

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Posted 2021-May-09, 16:19

View Postgszes, on 2021-May-09, 14:30, said:

With so little needed (from partner)to make game Axxxx xx T8 xxxx I feel compelled to try x. I was curious to see what the spoiler was going to bring.
After 4h x and with the opps having a 9/10+ card diamond fit AND heart shortness I feel playing around looking for a penalty just seems wrong. I intend to bid slam even if partner were to show me no key cards so I might as well try for 7 just in case partner has the heart AK. I am indeed willing to gamble p does not have a side ace vs the heart ace.

4n rkc fortunately I do not play or recommend those void showing variants since the information is rarely useful and it can backfire sometimes getting us too high.


And here lies the rub. The reason I posed the question was that overcalling 5 deprives you of the ace ask. I actually got the N hand wrong it's the same honours but 6/4 rather than 5-5.

This is the whole hand:



Nigel's decision of XX over 4x will lead to 4N from E, 5 from W and now N has a guess (6 ?) 7 is a good save unless NS bid 7.
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#10 User is offline   mikeh 

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Posted 2021-May-09, 16:43

I was trying to post earlier, but my phone died. Anyway, I think double of 4H is nuts, and not because Cyber was laying a trap, lol. We have negative defence and double gets passed far too often, and when it doesn’t it often leads to a poor 4-4 spade fit. AKJxxxx spells trump. 5D is clear, imo
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#11 User is online   Cyberyeti 

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Posted 2021-May-09, 17:07

View Postmikeh, on 2021-May-09, 16:43, said:

I was trying to post earlier, but my phone died. Anyway, I think double of 4H is nuts, and not because Cyber was laying a trap, lol. We have negative defence and double gets passed far too often, and when it doesn’t it often leads to a poor 4-4 spade fit. AKJxxxx spells trump. 5D is clear, imo


I wasn't laying a trap as such, I just noticed the unanticipated side effect. Give partner Q9xxx, xx, x, J9xxx and you may not enjoy the choice of 5 much while you might come out alive after X.

I'm glad after your post it wasn't unanimous.
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#12 User is offline   nullve 

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Posted 2021-May-10, 03:13

View Postmikeh, on 2021-May-09, 16:43, said:

I was trying to post earlier, but my phone died. Anyway, I think double of 4H is nuts, and not because Cyber was laying a trap, lol. We have negative defence and double gets passed far too often, and when it doesn’t it often leads to a poor 4-4 spade fit. AKJxxxx spells trump. 5D is clear, imo

Dealer script:
predeal west SKT62, DAKJ9642, CQT
condition hearts(south)>= 8 and spades(east)==4
produce 100
action average "avg. # of tricks if W is declarer in a D contract" (tricks(west,diamonds)), average "avg. # of tricks if East is declarer in a S contract" (tricks(east,spades))

One run:
avg. # of tricks if W is declarer in a D contract: 10.28
avg. # of tricks if East is declarer in a S contract: 9.81
Generated 31453 hands
Produced 100 hands
Initial random seed 1620637123
Time needed   13.130 sec

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#13 User is offline   Douglas43 

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Posted 2021-May-10, 05:30

View PostCyberyeti, on 2021-May-09, 17:07, said:

I wasn't laying a trap as such, I just noticed the unanticipated side effect. Give partner Q9xxx, xx, x, J9xxx and you may not enjoy the choice of 5 much while you might come out alive after X.

I'm glad after your post it wasn't unanimous.


I misread the spoiler and thought that the black two suiter was partner's hand, which is what usually happens when I bid 5. Now feeling much happier!
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#14 User is offline   mikeh 

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Posted 2021-May-10, 06:44

View Postnullve, on 2021-May-10, 03:13, said:

Dealer script:
predeal west SKT62, DAKJ9642, CQT
condition hearts(south)>= 8 and spades(east)==4
produce 100
action average "avg. # of tricks if W is declarer in a D contract" (tricks(west,diamonds)), average "avg. # of tricks if East is declarer in a S contract" (tricks(east,spades))

One run:
avg. # of tricks if W is declarer in a D contract: 10.28
avg. # of tricks if East is declarer in a S contract: 9.81
Generated 31453 hands
Produced 100 hands
Initial random seed 1620637123
Time needed   13.130 sec


You don’t understand my argument.

If I knew that partner had 4+ spades I’d double, since much of the time he’d have reasonably good spades and often 5+.

The biggest downside to doubling isn’t that we play spades rather than diamonds. It’s that I’m going to be on lead against 4H doubled, with far less defence than double suggests.

There is also the fact that sometimes a 4-4 spade fit, when he has bad spades, may play very poorly, since It may prove impossible to establish and run diamonds.

Oh, and what a way to run a simulation! You give opener at least 8 hearts. In today’s game, 4H doesn’t promise 8 hearts, even vulnerable. But more to the point you specified partner having 4S. That’s enough to invalidate your simulation. How the heck do you, looking at this hand sitting over a 4H opening, ‘know’ that partner has at least 4 spades?


Why not run a simulation that reflects reality? Of course, one of the weaknesses of simulations is that it can be difficult to set the constraints. Opener will often hold 8 hearts, but sometimes 9 or even 10, but also some 7 card suits, especially if, say, 7=4.

And the other main weakness is that you have to look at every hand to assess what partner will do. Will he pass? Will he bid 4N? Will he move towards slam?

Now, if your point, for some strange reason, was to assess whether a 4-4 spade fit will lead to a better result for double than would overcalling 5D when partner has 4 spades, I guess you win. Personally, I generally don’t know that much about partner’s hand thus early in the auction.
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#15 User is offline   LBengtsson 

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Posted 2021-May-10, 11:56

View Postmikeh, on 2021-May-09, 16:43, said:

I was trying to post earlier, but my phone died. Anyway, I think double of 4H is nuts, and not because Cyber was laying a trap, lol. We have negative defence and double gets passed far too often, and when it doesn’t it often leads to a poor 4-4 spade fit. AKJxxxx spells trump. 5D is clear, imo


agree and disagree. if the opening pre-empt is 4 as opposed to 4 partner has less choosing. however, we have to keep a contract of 4 in the mix on this hand. yes, we can end up in poor 4-4 fit if you X with west hand (agree) but disagree that 5 is a better bid. you can still run to 5 after X but you make it difficult for fit to be found once you bid 5 direct over 4.
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#16 User is offline   nullve 

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Posted 2021-May-10, 14:05

View Postmikeh, on 2021-May-10, 06:44, said:

Now, if your point, for some strange reason, was to assess whether a 4-4 spade fit will lead to a better result for double than would overcalling 5D when partner has 4 spades

Yes, that was the point.

View Postmikeh, on 2021-May-10, 06:44, said:

The biggest downside to doubling isn’t that we play spades rather than diamonds. It’s that I’m going to be on lead against 4H doubled, with far less defence than double suggests.

Agree.

View Postmikeh, on 2021-May-10, 06:44, said:

In today’s game, 4H doesn’t promise 8 hearts, even vulnerable.

[...]

Why not run a simulation that reflects reality? Of course, one of the weaknesses of simulations is that it can be difficult to set the constraints. Opener will often hold 8 hearts, but sometimes 9 or even 10, but also some 7 card suits, especially if, say, 7=4.

I was pretty sure it wouldn't help your argument if I included more shapes.

Anyway, here's an improved script:
predeal west SKT62, DAKJ9642, CQT
condition (hearts(south)>= 8 or (hearts(south)==7 and (clubs(south)>=4 or diamonds(south)>=4))) and spades(east)==4
produce 1000
action average "avg. # of tricks if W is declarer in a D contract" tricks(west,diamonds), average "avg. # of tricks if East is declarer in a S contract" tricks(east,spades)

One run:
avg. # of tricks if W is declarer in a D contract: 10.169
avg. # of tricks if East is declarer in a S contract: 9.903
Generated 150360 hands
Produced 1000 hands
Initial random seed 1620676152
Time needed   90.370 sec

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#17 User is offline   nige1 

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Posted 2021-May-11, 16:05

A variation on Nullve's simulation, illustrating that
  • 4 is a good contract when East has a fit, and
  • South is quite likely to make 4X.

For more reliable numbers, bump the produce count.
predeal west SKT62, DAKJ9642, CQT
condition 
spades (east) > 3 and (hearts(south) > 7 
or (hearts (south) == 7 and (clubs (south) > 3 or diamonds (south) > 3))) 
produce 100
action 
frequency "D tricks by W" (tricks (west, diamonds), 11, 11),
frequency "S tricks by E" (tricks (east, spades), 10, 10),
frequency "H tricks by S" (tricks (south, hearts), 10, 10)



Frequency D tricks by W:
Low      	48   
11      	36
High      	16
Frequency S tricks by E:
Low      	25   
10      	22
High      	53
Frequency H tricks by S:
Low      	38   
10      	30
High      	32
Generated 7941 hands
Produced 100 hands
Initial random seed 1620769811
Time needed   33.437 sec

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#18 User is offline   mikeh 

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Posted 2021-May-11, 21:18

View Postnige1, on 2021-May-11, 16:05, said:

A variation on Nullve's simulation, illustrating that
  • 4 is a good contract when East has a fit, and
  • South is quite likely to make 4X.

For more reliable numbers, bump the produce count.
predeal west SKT62, DAKJ9642, CQT
condition 
spades (east) > 3 and (hearts(south) > 7 
or (hearts (south) == 7 and (clubs (south) > 3 or diamonds (south) > 3))) 
produce 100
action 
frequency "D tricks by W" (tricks (west, diamonds), 11, 11),
frequency "S tricks by E" (tricks (east, spades), 10, 10),
frequency "H tricks by S" (tricks (south, hearts), 10, 10)



Frequency D tricks by W:
Low      	48   
11      	36
High      	16
Frequency S tricks by E:
Low      	25   
10      	22
High      	53
Frequency H tricks by S:
Low      	38   
10      	30
High      	32
Generated 7941 hands
Produced 100 hands
Initial random seed 1620769811
Time needed   33.437 sec


I have no idea why anyone would feel the need to run a simulation to determine whether 4S would be a good spot, most of the time, if east has 4 or more. I would have thought it self evident, although it is equally self-evident that xxxx is unlikely to make for a good contract...in spades or diamonds, although xxxx xx Qx AJ9xx makes a diamond contract pretty good...and I don't need a simulation to prove that, lol.

Run a proper simulation, giving opener 7+ hearts...if 7 then not 7222 and always, if 7, very good hearts...at least AKJ10xxx and likely, then, either some 7330 or some 74 hand...even then there would be hands some would say fit and some would say don't. Make it too good, and one may have a 1H opener. Make it too weak and one might have a 3H opener.

Then look at each hand...what would LHO do, over double (directly or after passing and having advancer bid)? What will advancer do?

Nobody can be objective, btw, doing this, if they know our hand.

So simulations, which have very powerful uses in some scenarios, are essentially worthless here, if the desire is to prove what action is best. I doubt that I'd agree with nullve or nige's selection of hands and actions for the other players...not that my views would be entitled to any deference, but simply because these judgement calls are never unanimous. Heck, in discussions with two of my long time partners, both multiple national champions, and we play similar methods in the 2 partnerships, we don't agree on all choices even on simpler hands than this.

At the end of the day, one relies on one's own experiences and biases. Mine tell me that x is too high a risk, not because of a fear of spades (though on a bad day spades is going for a number and is the only contract LHO can double) but because, added to the risk of a poor spade contract, and far more importantly, partner won't expect so little defence for double and will pass far too often...or drive too high in a black suit.

As I said before: if all I knew was that partner held 4+ spades, I'd bid x in a heartbeat. Lacking that information, I bid 5D
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#19 User is offline   Winstonm 

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Posted 2021-May-11, 22:09

View Postmikeh, on 2021-May-11, 21:18, said:

I have no idea why anyone would feel the need to run a simulation to determine whether 4S would be a good spot, most of the time, if east has 4 or more. I would have thought it self evident, although it is equally self-evident that xxxx is unlikely to make for a good contract...in spades or diamonds, although xxxx xx Qx AJ9xx makes a diamond contract pretty good...and I don't need a simulation to prove that, lol.

Run a proper simulation, giving opener 7+ hearts...if 7 then not 7222 and always, if 7, very good hearts...at least AKJ10xxx and likely, then, either some 7330 or some 74 hand...even then there would be hands some would say fit and some would say don't. Make it too good, and one may have a 1H opener. Make it too weak and one might have a 3H opener.

Then look at each hand...what would LHO do, over double (directly or after passing and having advancer bid)? What will advancer do?

Nobody can be objective, btw, doing this, if they know our hand.

So simulations, which have very powerful uses in some scenarios, are essentially worthless here, if the desire is to prove what action is best. I doubt that I'd agree with nullve or nige's selection of hands and actions for the other players...not that my views would be entitled to any deference, but simply because these judgement calls are never unanimous. Heck, in discussions with two of my long time partners, both multiple national champions, and we play similar methods in the 2 partnerships, we don't agree on all choices even on simpler hands than this.

At the end of the day, one relies on one's own experiences and biases. Mine tell me that x is too high a risk, not because of a fear of spades (though on a bad day spades is going for a number and is the only contract LHO can double) but because, added to the risk of a poor spade contract, and far more importantly, partner won't expect so little defence for double and will pass far too often...or drive too high in a black suit.

As I said before: if all I knew was that partner held 4+ spades, I'd bid x in a heartbeat. Lacking that information, I bid 5D


Mike, I had the same qualms about double - but I would rather play at the 4-level than 5-level. I've almost convinced myself that pass has a lot of merit because this hand really isn't all that good. At mps I bid - what the heck. At imps, I feel screwed no matter what I do.

So my question is: how do you rate pass?
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#20 User is offline   mikeh 

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Posted 2021-May-12, 00:06

View PostWinstonm, on 2021-May-11, 22:09, said:

Mike, I had the same qualms about double - but I would rather play at the 4-level than 5-level. I've almost convinced myself that pass has a lot of merit because this hand really isn't all that good. At mps I bid - what the heck. At imps, I feel screwed no matter what I do.

So my question is: how do you rate pass?

If I had to pass at any form of scoring, it would be mps, but I’d not pass at any form of scoring.

Imps risks a double game swing. Picture partner with Qx xxx Qxxx KJxx. We’re cold for 5D while they’re cold for 4H if opener has 8 hearts...8 hearts and two black aces. Mps, it’s only a board. Btw, if we double and catch partner with that hand, we’re minus 790. Into our 600....obviously we can equally generate hands where double wins big, so I’m not pretending this is likely.

I’m not a fan of Bobby Wolff....despite his being a great player....but I do like a saying he used in the BW MSC, on numerous occasions....hands like these are ‘too dangerous to pass’

Remember...LHO doesn’t know your hand, especially when you bid 5D. For all he knows you have 8 diamonds. He’s more likely to take the push to 5H over 5D than over double, especially if he’s loaded in spades (when passing the double might give him a shot at 4S)

Admittedly that’s a tiny, maybe non-existent, edge against good players who know that they bid immediately or not at all.
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