Easy 4S - Assign the Blame

[kenrexford]

While it's really tempting to raise to game on the North cards anyway, I really think you shouldn't.

 

The last few times I've raised it's gone 1 or 2 off, and partner has pointed out that he had xx, 2NT, 3C, 3D, 3H as game tries and that I wasn't invited to bid.

Yeah, but partner's 3♠ bid preempted you out of many of your own game tries. Plus, 3♠ usually shows a hand, in an auction like this, that is not right for a game try but is right to accept a game try.

Game tries after raising 1S to 2S?

Yeah, why not?

 

I mean, if it is possible for any person to raise 1♠ to 2♠, and then later to bid 3♠, why would that person not make a game try on route to the "forced" 3♠ if game is possible?

 

I see that happen fairly often, actually. No one can really make a legitimate GT, for fear of losing the +110. However, the opponents force us to make a decision to commit to nine tricks. Well, in that situation, showing what you wanted to show but were wise to not show now makes sense.

 

The funny thing is that this deal proves my point. Had Opener been provided the decision whether to bid 3♠, he would bite. If he could bid 3♣ on route to 3♠, great!

[mike777]

North 100%

wtp?

[rogerclee]

North 100%

wtp?

Wow, much more convincing the second time around.

[hotShot]

To support my instincts with numbers, I've been doing a little simulating.

My instincts told me that opener can't have 4♥ and that the bidding reduces his ♦ length a lot.

 

North showed 3+♣,  4♠ and should not have 4♥.

South has 5♠ and 4♦ and he can conclude that his partner is short (0-1) in ♦.

Note that with the given definition for he 1♣ opening the only unbalanced hand with 4441 shape has a single ♦.

 

So, starting again, how does South know that North has 0-1 diamonds, and why can't North have Axxx Qxxx Kx Kxx ?

 

Defining the opening:

Balanced: 2-4M, 2-5m and 12-14 HCP (not 5♦4♣ or 4♦4♣ assuming an 1♦ opening for these)

unbalanced with Clubs: 0-4M, 0-3♦ and 4+♣

Information for South [space]Average length in
_______________ [space][cl] [space] [space] [space] [space][di] [space] [space] [space] [he] [space] [space] [space] [space] [space][sp]
Opening_____ 4.4768 [space] 2.4381 [space] 3.0455 [space] [space] 3.0396
East has 5+[di] 4.5797 [space] 2.2396 [space] 3.0888 [space] [space] 3.0918
South has 4[di] 4.7220 [space] 1.9580 [space] 3.1442 [space] [space] 3.1759
North has 4[sp] 4.2634 [space] 1.7872 [space] 2.9494 [space] [space] 4.0000
South has 5[sp] 4.2414 [space] 1.7310 [space] 3.0276 [space] [space] 4.0000

As you can see from the numbers, opener will usually have 4-5♣, if opening 1♣. We don't expect opener to hold a 4 card-major most of the time and even less to hold 4 cards in both majors. Informations gained from the bidding reduces the expected ♦ length, but I overestimated that effect.

 

This is one of the rare (or not so rare) cases where one side has a 9 card fit, while the other side does not even have a fit at all. (9666 opposite 4777).

[gnasher]

I had something really dull to do this morning, so instead I did my own simulation. The differences are:

- My criteria for 1♣ are slightly different

- South's hand is exactly specified

- East's hand is constrained to look like a takeout double

- North doesn't have a raise to 3♠ or more (crudely defined as 16+ or 0-5 losers *)

- West doesn't have a raise to 2♦

- I computed the likelihoods of North's having four hearts and short diamonds, rather than the average lengths

 

* Please note that this isn't intended as an endorsement of LTC as a method of hand evaluation.

 

The results for 10000 hands were:

 0-3 hearts                 6965

 0-1 diamonds               1941

 Both                       1049

 

Here is the code that I used, using Thomas Andrews's "Deal" program:

 

source format/none

south is {Q9632 A6 JT82 J4}

# Counters
set Not_4H 0
set Short_D 0
set Both 0

main {
[space]if {[spades north] != 4} {
[space] [space]reject
[space] [space]}
[space] [space]
[space]# "losers" computes 2x standard LTC.
[space]if {! [1c north] || [hcp north] > 15 || [losers north] < 12} {
[space] [space]reject
[space] [space]}
[space] [space]
[space]if {! [1d_and_dbl_1s east]} {
[space] [space]reject
[space] [space]}
[space] [space]
[space]# West didn't raise
[space]if { [diamonds west] > 2 && [hcp west] > 4} {
[space] [space]reject
[space] [space]}
[space] [space]
[space]if {[hearts north] < 4} {
[space] [space]incr Not_4H

[space] [space]if {[diamonds north] < 2} {
[space] [space] [space]incr Both
[space] [space] [space]}
[space] [space]}
[space]
[space]if {[diamonds north] < 2} {
[space] [space]incr Short_D
[space] [space]}
[space] [space]
[space]accept
}

proc 1c {hand} {
[space]set hcp [hcp $hand]
[space]
[space]if {[balanced $hand]} {
[space] [space]if {$hcp > 11 && $hcp < 15} {
[space] [space] [space]accept
[space] [space] [space]}
[space] [space]
[space] [space]reject
[space] [space]}
[space] [space]
[space]set club_len [clubs $hand]

[space]# 11+, clubs longer than anything else (note: this includes (422)5 and (322)6 regardless of range)
[space]if {$hcp > 10 && $hcp < 21 && 
[space] [space] [space]$club_len > [spades $hand] && 
[space] [space] [space]$club_len > [hearts $hand] && 
[space] [space] [space]$club_len > [diamonds $hand] } {
[space] [space]accept
[space] [space]}

[space]# 12+, 4441 type
[space]if {$hcp > 11 && 
[space] [space] [space]$club_len == 4 &&
[space] [space] [space][$hand pattern] == "4 4 4 1"} {
[space] [space]accept
[space] [space]}

[space]reject
[space]}
[space]
proc 1d_and_dbl_1s {hand} {
[space]if {[diamonds $hand] < 5 || [hcp $hand] < 13} {
[space] [space]reject
[space] [space]}
[space] [space]
[space]set s [spades $hand]
[space]set h [hearts $hand]
[space]set c [clubs $hand]
[space]
[space]if {$h > 4 || $c > 4} {
[space] [space]reject
[space] [space]}
[space]
[space]# 1 3+ 5= 3+
[space]if {$s < 2 && $h > 2 && $c > 2} {
[space] [space]accept
[space] [space]}
[space] [space]
[space]# 2452
[space]if {$h == 4 && $c == 2} {
[space] [space]accept
[space] [space]}
[space]
[space]reject
[space]}

deal_finished {
[space]puts " 0-3 hearts [space] [space] [space] [space] [space] [space] [space] [space] $Not_4H"
[space]puts " 0-1 diamonds [space] [space] [space] [space] [space] [space] [space] $Short_D"
[space]puts " Both [space] [space] [space] [space] [space] [space] [space] [space] [space] [space] [space] $Both"
}

[hotShot]

Thanks for posting the script, so I could rerun it and use the statistic to calculate average suit length. The added code is:

# Average suit length
sdev CL_length
sdev DI_length
sdev HE_length
sdev SP_length

CL_length add [clubs north]
DI_length add [diamonds north]
HE_length add [hearts north]
SP_length add [spades north]


puts "Average length CL:[CL_length average] DI:[DI_length average]" 
puts " [space] [space] [space] [space] [space] [space] [space] HE:[HE_length average] SP:[SP_length average]"

Your results:

The results for 10000 hands were:

0-3 hearts                 6965

0-1 diamonds               1941

Both                       1049

My run of 10000 hands:

0-3 hearts                 6967

0-1 diamonds               2014

Both                       1143

Average length CL:3.9638 DI:2.1039

               HE:2.9323 SP:4.0

Your average ♦ length is higher, because you added:

- West doesn't have a raise to 2♦

Adding that condition I get: 4.0000 2.0926 2.9074 4.0000

[dbsboy]

No Blame, I'd say.

 

If East doesn't bid 1D, it must end in 2S.

 

Typical Part Score with some uptricks

[catatonic]

with a major suit fit I am no longer interested in point count

 

with this 6 loser hand I will rebid 3 spades , not 2

if pt has 8 losers he can bid 4 ...and here he has

of course , if I have something like AQx of diamonds I will devalue

[kenrexford]

I thought that bidding 4♠ with the North hand was right because it just felt right. Now I don't know. I forgot to consider a few things:

 

1. ♥=(8.3440):♦-♣

2. 2.0026 4.2200 2.1115 hut hut hike

3. One potato two potato three potato go

4. Watch very carefully...at no point to my hands leave my arms.

 

Now, I'm not sure what to bid.