math or simulation for this
#1
Posted 2014-December-22, 07:00
♠AQJ
♥J93
♦KQ108
♣J64
Partner bids 2♣-2♦-2♥ showing at least 5-4 in the majors and a weak hand (less than 9)
Will partner have more hearts or spades on average?
#2
Posted 2014-December-22, 07:12
Fluffy, on 2014-December-22, 07:00, said:
♠AQJ
♥J93
♦KQ108
♣J64
Partner bids 2♣-2♦-2♥ showing at least 5-4 in the majors and a weak hand (less than 9)
Will partner have more hearts or spades on average?
Hearts, I think, because if the spades are any good partner might have bid 2♠ over 2♦ (if available) or transferred initially.
EDIT: similarly, if the default is to bid rebid hearts with 3-3, then with 4-5 partner is guaranteed to find an 8-card fit if there is one. With 5-4 there is no such guarantee, so less of a reason to keep hearts in the picture.
#3
Posted 2014-December-22, 07:12
#4
Posted 2014-December-22, 07:13
My guess would be ♥s, since if he had 4, there's a chance opps would have overcalled in the suit, which looks much less likely in ♠s.
#5
Posted 2014-December-22, 07:29
Vampyr, on 2014-December-22, 07:12, said:
Really can't even begin to answer this question without knowing what other options partner had (for me 2♥ would have shown much the same but 2♠ would have been invitational with 5 spades).
-- Bertrand Russell
#6
Posted 2014-December-22, 08:44
they will not use this particular system with 4 lousy hearts and 5 lousy spades
vastly preferring to transfer to spades in that situation since it is quite
risky taking a chance on playing a lousy 7 card heart fit and missing a lousy
8 card spade fit. Responder will have no qualms with 4 lousy spades and 5 lousy
hearts since there is no risk of missing the 8 card heart fit.
Hearts should have 5 more frequently than spades but how often is a matter of
personal taste. Where would you draw the line between a simple transfer and
using stayman with the following hands?
AKQ2 87654 32 32
AK32 87654 32 32
AQ32 87654 32 32
QJT2 87654 32 32
and will your answer depend on vulnerability?
#7
Posted 2014-December-22, 09:04
Probably the real question is "should I keep playing this system?", to which I would firmly say "no".
#8
Posted 2014-December-22, 09:19
Fluffy, on 2014-December-22, 07:00, said:
♠AQJ
♥J93
♦KQ108
♣J64
Partner bids 2♣-2♦-2♥ showing at least 5-4 in the majors and a weak hand (less than 9)
Will partner have more hearts or spades on average?
I'm assuming that partner will bid like this EVERY time he has 54+ in the majors and less than 9.
There are more unknown x's in spades, so there are more ways to construct a weak hand with 5(+)spades than 5(+)hearts.
#10
Posted 2014-December-22, 09:46
If not, both patterns are equally likely.
#11
Posted 2014-December-22, 09:48
Jinksy, on 2014-December-22, 07:13, said:
Fluffy, on 2014-December-22, 07:00, said:
You can discount 6-4, 7-5 and 7-4 I guess but I don't think they are going to change which suit is longer if any.
#12
Posted 2014-December-22, 10:35
But simulation shows:
$ cat simu.descr predeal north SAQJ,HJ93,DKQT8,CJ64 condition shape(south, 54xx + 45xx + 55xx) && hcp(south) < 9 action frequency "heart length" (hearts(south),4,5), frequency "spade length" (spades(south),4,5), $ ./dealer < simu.descr Frequency heart length: 4 140195 5 164470 Frequency spade length: 4 124103 5 180562 Generated 10000000 hands Produced 304665 hands Initial random seed 1419266048 Time needed 3.185 sec
So more small cards in spades makes spade length more likely because of hcp limits.
#13
Posted 2014-December-22, 10:56
suokko, on 2014-December-22, 10:35, said:
But simulation shows:
$ cat simu.descr predeal north SAQJ,HJ93,DKQT8,CJ64 condition shape(south, 54xx + 45xx + 55xx) && hcp(south) < 9 action frequency "heart length" (hearts(south),4,5), frequency "spade length" (spades(south),4,5), $ ./dealer < simu.descr Frequency heart length: 4 140195 5 164470 Frequency spade length: 4 124103 5 180562 Generated 10000000 hands Produced 304665 hands Initial random seed 1419266048 Time needed 3.185 sec
So more small cards in spades makes spade length more likely because of hcp limits.
Were this the only variable factor, it would be a slam dunk.
However, it ignores the opponent's bidding. With a borderline hand, depending on methods, an opponent would be more likely to enter the bidding with a chunky 4 card major plus a 5-card minor, for instance. And they can't only have a chunky major if it is hearts. The argument also holds with 5M4m hands.
Also, assuming OP plays Stayman followed by 2♠ as invitational with five, there is a gap when holding the equivalent hand with 9 points and 45 in the majors. It is quite rational to go low and bid Stayman followed by 2♥ with that agreement.
Having said all that, my gut instinct is that the spade blockers trump my arguments.
#14
Posted 2014-December-22, 11:11
PhilKing, on 2014-December-22, 10:56, said:
However, it ignores the opponent's bidding. With a borderline hand, depending on methods, an opponent would be more likely to enter the bidding with a chunky 4 card major plus a 5-card minor, for instance. And they can't only have a chunky major if it is hearts. The argument also holds with 5M4m hands.
Also, assuming OP plays Stayman followed by 2♠ as invitational with five, there is a gap when holding the equivalent hand with 9 points and 45 in the majors. It is quite rational to go low and bid Stayman followed by 2♥ with that agreement.
Having said all that, my gut instinct is that the spade blockers trump my arguments.
I never even try to make perfect simulation that takes all unlikely parameters into account. To me opponents passing in this situation is balanced enough effect to both lengths. It would probably have more effect to hcp frequency for south making the lowest values less likely. Of course that reduces slightly spade blockers effect but it isn't going to reverse the effect.
#15
Posted 2014-December-23, 00:50
Also responder pts matter here, with some values like 6-8 pts maybe he can play it safe and transfer knowing 2M in a 5-2 fit is less likely to go down, the main fear would be to avoid the 4-3. The cost of missing the 4-4 is lower. With a weaker hand however aiming for the 4-4 fit has more upside since it could be your only hope to get a plus score.
Also maybe with (54)22, 6-8 pts and poor majors maybe passing 1NT is the percentage call at imps if you play GS as 54 or 45.
For instance, he doesn't like being used as a human shield when we're being shot at.
I happen to think it's a very noble way to meet one's maker, especially for a guy like him.
Bottom line is we never let that difference of opinion interfere with anything."
#16
Posted 2014-December-23, 12:22
As I know a fair amount about statistics and computers I will provide you with an analogy. I bought a lucky dip lottery ticket once and the computer-generated ticket was 6 consecutive numbers! The point I'm making is that simulations are only that, they cannot compete with raw statistics. I was very unlikely to ever win with that ticket BUT it is one of the 14 or so million combinations of numbers that are available, so it actually stands just as much chance as any other ticket in theory.
If you partner ALWAYS bids 2♣ with any 5-4 majors of less than 9 points, and does not deviate from that premise, whatever cards and honour cards he holds, there is an equal chance of him holding 5♥/4♠ or 4♥5♠.
However, if he has AN ADDITIONAL OPTION to make a major suit transfer if he has honour cards in a suit, then he is more likely to have a 5 card ♠ suit on probabilities.
#17
Posted 2014-December-23, 12:35
You can play the other way around for sure, for example if you think it's better that the weak hand declares (unknown strength).
Without such agreement, chances are equal.
#18
Posted 2014-December-23, 16:37
The_Badger, on 2014-December-23, 12:22, said:
If you partner ALWAYS bids 2♣ with any 5-4 majors of less than 9 points, and does not deviate from that premise, whatever cards and honour cards he holds, there is an equal chance of him holding 5♥/4♠ or 4♥5♠.
This statement is "true", but it is not true when we hold this hand for the reason given by Radrag and Suokkoi.
There are more combinations of weak hands containing 5 spades than there are holding 5 hearts. In a word, "blockers". If you don't trust simulations you can do it this way - put the missing cards in three piles: spades, hearts and minors. Then deal four cards from each pile then mix the remaing major cards and deal one card. You will find more heart hands invalidated for being too strong than vice versa.
#19
Posted 2014-December-23, 16:40
Fluffy, on 2014-December-22, 07:00, said:
♠AQJ
♥J93
♦KQ108
♣J64
Partner bids 2♣-2♦-2♥ showing at least 5-4 in the majors and a weak hand (less than 9)
Will partner have more hearts or spades on average?
If you're playing a weak version of Stayman where you can bid 2C with 54 in the majors (either suit longer) then you should always bid your five card major on this sequence.
1NT - 2C - 2D - 2H should promise five+ hearts.
Partner does not have a four card major and a 5-2 fit plays better than a 4-3 fit. You might still have a fit in your five card major but you definitely don't in your four card suit. So just agree to bid the longer one, its simple if you do that. This is the standard approach in the UK.
#20
Posted 2014-December-23, 16:52
SixOfWands, on 2014-December-23, 16:40, said:
1NT - 2C - 2D - 2H should promise five+ hearts.
Partner does not have a four card major and a 5-2 fit plays better than a 4-3 fit. You might still have a fit in your five card major but you definitely don't in your four card suit. So just agree to bid the longer one, its simple if you do that. This is the standard approach in the UK.
Obviously if you can bid 2S showing 5S and 4H weak you don't need to play this way. Some people use 2C then 2S as something more important than that hand type and sacrifice accuracy on weak 5/4 hands for gains on others.