[Cascade]

lmilne, on Apr 15 2010, 05:59 PM, said:

Wow, everyone thinks that 6♣ is the best MP bid playing no system? Playing in a weakish field with no system, I bid 3NT as it looked like the biggest chance for a good plus, whereas 6♣ risks a minus that I really don't need with weak players having my cards around the room. 6♣ does make, but +720 (on a heart lead into the AQ) was a pretty hot score regardless.

Can anyone be bothered to do a sim to see how many tricks are likely with clubs as trumps opposite 20-22?

I got

65.4% chance of 12 or 13 double dummy tricks with the club hand as declarer

70.5% chance of 12 or 13 double dummy tricks with the strong hand as declarer

[qwery_hi]

I remember some top pairs playing 2NT - 4H single suited slam try in clubs, and 4S as single suited slam try in diamonds, but may be wrong.

[Cascade]

Cascade, on Apr 15 2010, 06:18 PM, said:

lmilne, on Apr 15 2010, 05:59 PM, said:

Wow, everyone thinks that 6♣ is the best MP bid playing no system?  Playing in a weakish field with no system, I bid 3NT as it looked like the biggest chance for a good plus, whereas 6♣ risks a minus that I really don't need with weak players having my cards around the room.  6♣ does make, but +720 (on a heart lead into the AQ) was a pretty hot score regardless.

Can anyone be bothered to do a sim to see how many tricks are likely with clubs as trumps opposite 20-22?

I got

65.4% chance of 12 or 13 double dummy tricks with the club hand as declarer

70.5% chance of 12 or 13 double dummy tricks with the strong hand as declarer

The numbers were slightly smaller when i included some slightly offshape hands (4441 with stiff honour and 5422s but not both majors).

64.0%

68.6%

[qwery_hi]

qwery_hi, on Apr 14 2010, 11:39 PM, said:

I remember some top pairs playing 2NT - 4H single suited slam try in clubs, and 4S as single suited slam try in diamonds, but may be wrong.

Well, a bit of googling turned up :

Lauria - Versace 2007 BB :

2NT - 4C = 6+ hearts slam try
4D = 6+ spades ..
4H, 4S ditto.

[gnasher]

qwery_hi, on Apr 15 2010, 08:45 AM, said:

qwery_hi, on Apr 14 2010, 11:39 PM, said:

I remember some top pairs playing 2NT - 4H single suited slam try in clubs, and 4S as single suited slam try in diamonds, but may be wrong.

Well, a bit of googling turned up :

Lauria - Versace 2007 BB :

2NT - 4C = 6+ hearts slam try
4D = 6+ spades ..
4H, 4S ditto.

I do that too, so I could bid 4♥ and then stop in 5♣ (or 4NT) if partner denied suitability. But I'd prefer to just play 6♣ by opener on an uninformative auction.

Looking at Cascade's figures, and adding in the significant chance that it makes on the wrong lead, that seems best.

This post has been edited by gnasher: 2010-April-15, 02:13

[whereagles]

cherdanno, on Apr 14 2010, 09:27 PM, said:

whereagles, on Apr 12 2010, 02:22 PM, said:

If you lack the methods to investigate, just use the losing trick count. A 20-22 NT usually has 6 cover cards. You have 6 losers, you it's a simple

2NT 6♣

Good evaluation method! So you would do the same with xx xx xx AQxxxxx?

you got any better idea? I don't.

[dake50]

Xfer to C; show H-short. Partner has the helm.

[Cascade]

Simulations depending on partner's values (hcp) in hearts:

0 99.4% 99.4%
1 98.5% 97.8%
2 93.1% 91.0%
3 84.7% 79.2% (king)
3 85.8% 82.7% (queen-jack)
4 88.7% 83.7% (ace)
4 72.7% 69.4% (king-jack)
5 67.4% 62.6% (ace-jack)
5 64.1% 58.5% (king-queen)
6 63.3% 57.2% (ace-queen)
6 59.4% 55.8% (king-queen-jack)
7 63.5% 56.2% (ace-king)
7 57.0% 51.8% (ace-queen-jack)
8 53.2% 47.8%
9 46.7% 40.5%
10 36.2% 28%

The first column is the HCP
The second column is with the strong hand as declarer
The third column is with the weak hand as declarer

[Jlall]

How often is it necessary to play from partners side?

[Cascade]

Jlall, on Apr 16 2010, 04:16 PM, said:

How often is it necessary to play from partners side?

I edited to show this well actually explain how to read the information that was already there.

Enough to make it worth right siding I think.

[Jlall]

Cascade, on Apr 15 2010, 11:24 PM, said:

Jlall, on Apr 16 2010, 04:16 PM, said:

How often is it necessary to play from partners side?

I edited to show this well actually explain how to read the information that was already there.

Enough to make it worth right siding I think.

I see thanks

[FrancesHinden]

lmilne, on Apr 15 2010, 05:02 AM, said:

FrancesHinden, on Apr 14 2010, 03:32 PM, said:

2NT - 3NT (transfer to clubs)
4C - 6C

So the advantage of your system is transferring the contract? You're not interested in exploring controls or partner's club holding?

I was replying in a slightly concise manner to the various posters who suggested that the best approach on this hand is to get to 6C by partner in as uninformative a manner as possible.

I agree with them. There is a balance between bidding slam and making the opponents guess (and say leading a heart when partner's hand is Qxx AKx AKQxx Kx), and showing, for example, heart shortage and finishing in 4NT or 5C when partner has heart wastage (although my careful construction above might be better in 6C than 4NT anyway).

Quote

And I don't know what 6 cover cards means but that seems not to make a whole lot of sense.  On the other hand, if you have in fact solved the problem of constructive bidding, let me know...

Is sarcasm strictly necessary? Particularly as I never said anything about 'cover cards'

[Jlall]

Frances, no one would ever be sarcastic towards you!

I think the first paragraph that lmilne posted was directed to you, and the second was to whereagles (who had been talking about 6 cover cards).

I will admit that 2N-3N>clubs, 2N-4C>diamonds, and 2N-3S both minors has a ton of constructive merit, almost to the point where I would be willing to flip my view about 2N-3N being artificial. It just seems so good.

[FrancesHinden]

Cascade, on Apr 15 2010, 06:18 AM, said:

I got

65.4% chance of 12 or 13 double dummy tricks with the club hand as declarer

70.5% chance of 12 or 13 double dummy tricks with the strong hand as declarer

Isn't double dummy a not terribly helpful measure here? I'd expect 6C bid on an uninformation auction to make much more often single dummy than double dummy.

I guess (although you might be able to prove me wrong) that declarer will have fewer decisions in the play than the defence will have on opening lead.

[Jlall]

FrancesHinden, on Apr 16 2010, 03:15 AM, said:

Cascade, on Apr 15 2010, 06:18 AM, said:

I got

65.4% chance of 12 or 13 double dummy tricks with the club hand as declarer

70.5% chance of 12 or 13 double dummy tricks with the strong hand as declarer

Isn't double dummy a not terribly helpful measure here? I'd expect 6C bid on an uninformation auction to make much more often single dummy than double dummy.

I guess (although you might be able to prove me wrong) that declarer will have fewer decisions in the play than the defence will have on opening lead.

Well, lmilne was talking about bidding 2N-3N and questioning the merit of driving to slam if there are no methods. I think Cascades simulation has shown that bidding slam > bidding 2N-3N, since the double dummy considerations should make the % of making LOWER not higher as you point out, and it's well above 50 obv.

Of course it doesn't solve the debate about whether to just try or not, and whether to blast or not.

[Cascade]

FrancesHinden, on Apr 16 2010, 08:15 PM, said:

Cascade, on Apr 15 2010, 06:18 AM, said:

I got

65.4% chance of 12 or 13 double dummy tricks with the club hand as declarer

70.5% chance of 12 or 13 double dummy tricks with the strong hand as declarer

Isn't double dummy a not terribly helpful measure here? I'd expect 6C bid on an uninformation auction to make much more often single dummy than double dummy.

I guess (although you might be able to prove me wrong) that declarer will have fewer decisions in the play than the defence will have on opening lead.

I am not sure of the frequency of there being a double dummy advantage versus getting a bad lead.

However there are some situations where there is a double dummy advantage to offset some of the bad leads e.g. hearts that need to be set up - finesse or ruffing finesse or ruff out; stiff club king offside; and some combinations in side suits.

The more significant point of interest for me from the double dummy result was the edge that the strong hand had in being declarer.

[FrancesHinden]

Jlall, on Apr 16 2010, 08:18 AM, said:

I think Cascades simulation has shown that bidding slam > bidding 2N-3N, since the double dummy considerations should make the % of making LOWER not higher as you point out, and it's well above 50 obv.

Of course it doesn't solve the debate about whether to just try or not, and whether to blast or not.

Yes, true.

I did my own simulation of 50 hands and got the strong hand making 6C 75% of the time double dummy (which is sufficiently similar to Cascade's answer from a much smaller sample).

I then had a look at them single dummy. There were 6 hands where the lead determined the result (always when there were two top cashers but 12 tricks on the wrong lead), and 7 hands where there was a choice in the play. However on most of the 'play' hands, the opening lead may have resolved the choice for you.

On one hand I couldn't see how to make 6C double dummy even knowing that 12 tricks were cold (I counted that as a 6C-1 in my analysis!)

p.s on one hand 3NT was two off as well as opening leader had AKQxxx diamonds.

[Fluffy]

Cascade, on Apr 16 2010, 08:48 AM, said:

The more significant point of interest for me from the double dummy result was the edge that the strong hand had in being declarer.

5% difference, but that's on the right lead, with QJ10 makg the right lead is not so hard, but leading though the right King when prtner holds AQ or AJ is a different history. In practice I think this percentage will drop to 3-3.5%.



From the simulation it seems to me that my 3♠ convention will work pretty nicelly here (partner bids 3NT when not interested in 5m/6m, when he has many cards/hcp in the majors, or when he has too many quakcs).

[hanp]

Fluffy, on Apr 16 2010, 06:12 AM, said:

but leading though the right King when partner holds AQ or AJ is a different history.

This reminded me of a Terry Pratchet book I happened to be reading yesterday. At some point Nobby says to a criminal: "Don't move or you are geometry!", which causes some confusion.

I think people usually say that it is a different "story" Fluffy but I like yours better. And I agree of course.

[cherdanno]

Jlall, on Apr 16 2010, 03:18 AM, said:

FrancesHinden, on Apr 16 2010, 03:15 AM, said:

Cascade, on Apr 15 2010, 06:18 AM, said:

I got

65.4% chance of 12 or 13 double dummy tricks with the club hand as declarer

70.5% chance of 12 or 13 double dummy tricks with the strong hand as declarer

Isn't double dummy a not terribly helpful measure here? I'd expect 6C bid on an uninformation auction to make much more often single dummy than double dummy.

I guess (although you might be able to prove me wrong) that declarer will have fewer decisions in the play than the defence will have on opening lead.

Well, lmilne was talking about bidding 2N-3N and questioning the merit of driving to slam if there are no methods. I think Cascades simulation has shown that bidding slam > bidding 2N-3N, since the double dummy considerations should make the % of making LOWER not higher as you point out, and it's well above 50 obv.

Of course it doesn't solve the debate about whether to just try or not, and whether to blast or not.

Doesn't Cascade's second set of numbers resolve that question? Even with a lot of wastage in hearts, slam is still above 30%. I don't think there is a way to try for club slam, show short hearts, and have partner cooperate with holdings like KQ in hearts.