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Sense check

#1 User is offline   Cyberyeti 

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Posted 2017-December-17, 10:38

Teams - all vul



Partner opens a 2N maybe via 2 possibly with Kokish indicating 2 point range.

How good does this range need to be to bid on ?

22-23 = pass I suspect
23-24 ?
24-25 ?
25-26 = bid on I suspect
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#2 User is offline   rmnka447 

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Posted 2017-December-17, 12:59

At teams all vul, bidding 35%+ probable game is at least break even. Point count should be tempered by any other factors that may affect the value of the hand.

IMO, this hand is a pretty blah 2 count, I probably wouldn't push on opposite 22-23 count 2 NT. But with any higher 2 NT, I'd just bid 3 NT.

I'll give you a 2 point hand that opposite a 22-23, I wouldn't pass on:

109x J108x 109 J87x

This hand has a lot of valuable intermediate cards that are very critical to setting up and running suits opposite a big Hand at NT.
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#3 User is offline   ggwhiz 

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Posted 2017-December-17, 13:51

2nt via 2 and kokish is on my card, is passable and that's my choice.

With a 4-card major I would bid on and pray we have a fit there, a favorable lead and a horseshoe but very little confidence.
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#4 User is offline   Cyberyeti 

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Posted 2017-December-17, 14:04

View Postggwhiz, on 2017-December-17, 13:51, said:

2nt via 2 and kokish is on my card, is passable and that's my choice.

With a 4-card major I would bid on and pray we have a fit there, a favorable lead and a horseshoe but very little confidence.


Yes but what range would 2N via kokish show ?
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#5 User is offline   LBengtsson 

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Posted 2017-December-17, 15:29

hands where one hand has big points and other hand has small points usually play badly. no likeable entry so pass is maybe a sensible bid.
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#6 User is offline   Cyberyeti 

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Posted 2017-December-17, 15:45

I'd be interested to see a simulation opposite 23/24/25 balanced to see what the odds are.

I actually had the most perfectly fitting 24 you could wish for opposite, KQJx, AKQx, AQx, QJ so the Js and 10s fill all the holes.
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#7 User is offline   nige1 

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Posted 2017-December-17, 16:38

View PostCyberyeti, on 2017-December-17, 10:38, said:

Teams - all vul Partner opens a 2N maybe via 2 possibly with Kokish indicating 2 point range. How good does this range need to be to bid on?
22-23 = pass I suspect
23-24 ?
24-25 ?
25-26 = bid on I suspect
Modern partnerships tend to be economical with the truth about their notrump ranges. For example, they upgrade "good" 21 counts to 22. And so on. Assuming that partner is such a player, I rate:
  • Pass with 22-23.
  • Raise with more
If partner is a rare honest player who normally has his bid then, vul at teams, you should consider raising with 22-23, as well. Notrump contracts play best when the HCP are divided fairly equally between declarer and dummy. On the other hand, average defenders find it hard to play effectively when declarer's strong hand is concealed.
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#8 User is offline   johnu 

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Posted 2017-December-17, 17:12

A simulation on Dealmaster Pro said that opposite a:

Balanced 23 - 3NT makes 34%
Balanced 24 - 3NT makes 52%
Balanced 25 - 3NT makes 72%

Looks like the old rule of thumb of 26 HCP for 3NT holds true at least for this hand.

Based on simulations, anything with 24 HCP as the lower end should bid 3NT. 23-24 is at the lower limit for 3NT at IMPs, and below 50% at MPs. Some play 22-24 and that's a clear pass.
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#9 User is offline   ggwhiz 

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Posted 2017-December-17, 18:12

View PostCyberyeti, on 2017-December-17, 14:04, said:

Yes but what range would 2N via kokish show ?


22-23 tops. Any suit bid is forcing and 2nt is the only one that can be passed. I thought that was the whole purpose of playing kokish.
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#10 User is offline   Cyberyeti 

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Posted 2017-December-17, 18:32

View Postggwhiz, on 2017-December-17, 18:12, said:

22-23 tops. Any suit bid is forcing and 2nt is the only one that can be passed. I thought that was the whole purpose of playing kokish.


No, we play 2N good 19-21, 2/2N as 22-23, 2-kokish-2N 24-25, lots of people do it differently
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#11 User is offline   gszes 

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Posted 2017-December-17, 19:03

R we playing puppet?? this can make a huge difference since its all too easy to imagine a spade contract could be vastly superior to nt. w/o puppet i would bid 3n with 23/24 (why does p always have to have a min?) at IMPS but stick with 24+ at MP
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#12 User is offline   Cyberyeti 

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Posted 2017-December-18, 05:20

View Postgszes, on 2017-December-17, 19:03, said:

R we playing puppet?? this can make a huge difference since its all too easy to imagine a spade contract could be vastly superior to nt. w/o puppet i would bid 3n with 23/24 (why does p always have to have a min?) at IMPS but stick with 24+ at MP


Because 23 is MUCH more likely than 24 when you get to these sort of point counts, even 20-22 I've heard is about 50% to be 20.
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#13 User is offline   Zelandakh 

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Posted 2017-December-18, 05:39

View PostCyberyeti, on 2017-December-18, 05:20, said:

Because 23 is MUCH more likely than 24 when you get to these sort of point counts, even 20-22 I've heard is about 50% to be 20.

Even if 23 is 2/3 of the time and 24 1/3, John's numbers suggest 3NT is around 40%, which is good enough. And partner might even have a 5 card spade suit if we are going to try 3 on the way.
(-: Zel :-)
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#14 User is offline   Tramticket 

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Posted 2017-December-18, 06:16

View PostZelandakh, on 2017-December-18, 05:39, said:

John's numbers suggest 3NT is around 40%, which is good enough.


Only if vulnerable at IMPs. If non-vulnerable, I suggest that you want better odds.
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#15 User is offline   Cyberyeti 

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Posted 2017-December-18, 06:31

View PostZelandakh, on 2017-December-18, 05:39, said:

Even if 23 is 2/3 of the time and 24 1/3, John's numbers suggest 3NT is around 40%, which is good enough. And partner might even have a 5 card spade suit if we are going to try 3 on the way.


If partner has 24 with a decent 5 card spade suit he'd prob bid it as 25, he might bid 22 as 23, I think that's a red herring.
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#16 User is offline   Zelandakh 

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Posted 2017-December-18, 09:24

View PostTramticket, on 2017-December-18, 06:16, said:

Only if vulnerable at IMPs. If non-vulnerable, I suggest that you want better odds.

It is vulnerable at Teams - read the OP!
(-: Zel :-)
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#17 User is offline   Zelandakh 

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Posted 2017-December-18, 09:26

View PostCyberyeti, on 2017-December-18, 06:31, said:

If partner has 24 with a decent 5 card spade suit he'd prob bid it as 25, he might bid 22 as 23, I think that's a red herring.

The we would need a new simulation for 4 opposite 22 and 23 5(332) hands. My guess is that these would not have worse odds than for 3NT even without taking account of partner not necessarily upgrading all of them.
(-: Zel :-)
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#18 User is offline   johnu 

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Posted 2017-December-18, 16:48

View PostZelandakh, on 2017-December-18, 09:26, said:

The we would need a new simulation for 4 opposite 22 and 23 5(332) hands. My guess is that these would not have worse odds than for 3NT even without taking account of partner not necessarily upgrading all of them.


For 23 HCP with 5 spades, 4 is 35%, and 3NT is 38% so it doesn't appear worthwhile to try for a 5-3 spade game since the NT game is marginally better on average, and looking for a major suit fit leaks information.

In any case, my estimate is that probably 90+% don't play a version of Puppet Stayman to find a 5 card major in opener's hand so a 5-3 spade fit isn't usually valuable for finding a spade contract.
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#19 User is offline   Cyberyeti 

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Posted 2017-December-21, 12:39

View Postjohnu, on 2017-December-18, 16:48, said:

For 23 HCP with 5 spades, 4 is 35%, and 3NT is 38% so it doesn't appear worthwhile to try for a 5-3 spade game since the NT game is marginally better on average, and looking for a major suit fit leaks information.

In any case, my estimate is that probably 90+% don't play a version of Puppet Stayman to find a 5 card major in opener's hand so a 5-3 spade fit isn't usually valuable for finding a spade contract.


We play 5 card non puppet stayman, it's very common to have a way of finding the 5-3 in this country although specifics vary.
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#20 User is offline   nige1 

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Posted 2017-December-22, 09:12

Thomas Andrew's program (dealer on BBO) is simple and versatile.
It can do double-dummy simulations.
It roughly confirms JohnU's simulation figures. For example
3N makes on roughly 39% of deals opposite a 23-24 HCP 2N opener.

/** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
tricks.ds. 22 Dec 2017. Nigel Guthrie. 
Trick expectation at double-dummy.
Dealer by Hans van Staveren & Henk Uijterwaal
http://dealergib1.bridgebase.com/tools/dealer/dealer.php
*** *** *** *** *** *** *** *** *** *** *** *** *** *** *** **/
predeal east ST52, HJ3, DJ742, CT842

# 2N opener
ntHCP = 23
wHCP = hcp (west)
w2N =
(shape (west, any 4333 + any 4432 + any 5332) and 
  (ntHCP == wHCP or wHCP == ntHCP + 1))
# Tricks test. 

produce 100
condition w2N
action
frequency "Tricks, West" (tricks( west, notrump), 8, 9),


Results
Frequency Tricks, West: 
Low      	21
 8 			40
 9 			31 
High   		8 
Generated 17554 hands 
Produced 100 hands 
Initial random seed 1513955813 
Time needed    4.351 sec

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