[jdeegan]

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There you see it. Odds on a 3-2 trump split. What do you think?

[jschafer]

I like to think that for both, the odds are over 68%.

[TWO4BRIDGE]

Who cares ?
You make 10 tricks even with a 4-1 split .

[AlexJonson]

I care.

I guess the issue is they play three rounds of diamonds, and what do we do.

[manudude03]

AlexJonson, on 2011-September-21, 16:03, said:

I care.

I guess the issue is they play three rounds of diamonds, and what do we do.

We ruff and play trumps claiming 10 if 4-1 break or 11 if 3-2.

[Foxx]

The exact odds of a 3-2 trump break is slightly less than 68% but it is usually quoted as 68% due to rounding. I don't know if this is the point jdeegan is looking for.

Whether the true practical odds on a 3-2 trump break, in this case, is 68% or something slightly different, it would stay the same if I were a novice, too.

[TWO4BRIDGE]

manudude03, on 2011-September-21, 16:22, said:

We ruff and play trumps claiming 10 if 4-1 break or 11 if 3-2.

Bingo !
After ruffing the 3rd Diam.....
If a 4-1 split is discovered on the 2nd round of trumps ( ♠ A and Q ), abandon trumps, clear the ♥A and K....... and start running the ♣ .
EDIT: you don't have to touch the Hearts.... just start on the Clubs

This post has been edited by TWO4BRIDGE: 2011-September-21, 16:41

[pooltuna]

jdeegan, on 2011-September-21, 15:32, said:

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There you see it. Odds on a 3-2 trump split. What do you think?

smaller but only by .00173913. However 32 trump breaks are only part of the odds story as far as making this hand goes.

[semeai]

jdeegan, on 2011-September-21, 15:32, said:

There you see it. Odds on a 3-2 trump split. What do you think?

More than 68%. With no information from the bidding, it's slightly under 68% at roughly 67.8%. If we assume, as a very simple first step, that neither East nor West has 7+ diamonds (necessarily to at least 4 honors!), then I calculate that that alone shifts the odds to 68.3%. If we assume neither East nor West has 6+ diamonds, that shifts the odds to 69.4%. I became bored there and stopped, but we should also exclude some hands with 6+ card heart suits and some hands where East has a 5 card red suit.

[aguahombre]

Layman's math: both our hands are 4-4-3-2. Both of our red suits are 3-2. The spades will break 3-2 more than normal expectation.

[semeai]

aguahombre, on 2011-September-21, 18:28, said:

Layman's math: both our hands are 4-4-3-2. Both of our red suits are 3-2. The spades will break 3-2 more than normal expectation.

No, the fact we're both 4-4-3-2 and our red suits are both 3-2 has nothing to do with it. The arrangement of the cards between our two hands (assuming this would still be the auction) has no effect on the expectation.

Correct layman's math: The opponents didn't bid despite some reasonable opportunities to overcall and some suits they hold both length and high cards in. Suits will break somewhat more often than the normal expectation.

[jdeegan]

aguahombre, on 2011-September-21, 18:28, said:

Layman's math: both our hands are 4-4-3-2. Both of our red suits are 3-2. The spades will break 3-2 more than normal expectation.

For sure. I am tempted to bring into the mix Pavlicek's hand generation machine. It would be a service for all us duplicate plodders to know what the real odds are when the opps deny 9-8-7 or possibly even 6 card suits.

[semeai]

jdeegan, on 2011-September-21, 21:25, said:

For sure. I am tempted to bring into the mix Pavlicek's hand generation machine. It would be a service for all us duplicate plodders to know what the real odds are when the opps deny 9-8-7 or possibly even 6 card suits.

What am I, chopped liver? (All right, I only excluded 6+ card diamond suits in my post above.)

Disallowing 6+ card suits for both East and West (can only be hearts or diamonds here), disregarding suit quality, I get 72.3% 71.9%

[Messed up my inclusion/exclusion: fixed -D to +D in the "code"]

Beware that 5 card suits with East on hands that would overcall over 1♣ will also have an effect but aren't included here, and some hands with 6 bad hearts, especially in West, that won't act are.

A = 10* (21 choose 11)+ 10*2*(-(13 choose 11) -8*(13 choose 10)- 28*(13 choose 9)-(13 choose 3)-8*(13 choose 4) - 28*(13 choose 5))
B = 5*(21 choose 12)+5*2*(-13-8*(13 choose 11) - 28*(13 choose 10) - (13 choose 4) - 8*(13 choose 5) - 28*(13 choose 6))
C = (21 choose 13)+2*(-1-8*13 - 28*(13 choose 11) - (13 choose 5) - 8*(13 choose 6) - 28*(13 choose 7)) 
D = 2*5*28*28+2*28*8
A/(A+B+C+D) = .719... (format works in wolfram alpha for your own web checking pleasure)

[jdeegan]

semeai, on 2011-September-21, 22:06, said:

What am I, chopped liver? (All right, I only excluded 6+ card diamond suits in my post above.)

Disallowing 6+ card suits for both East and West (can only be hearts or diamonds here), disregarding suit quality, I get 72.3%

Beware that 5 card suits with East on hands that would overcall over 1♣ will also have an effect but aren't included here, and some hands with 6 bad hearts, especially in West, that won't act are.

A = 10* (21 choose 11)+ 10*2*(-(13 choose 11) -8*(13 choose 10)- 28*(13 choose 9)-(13 choose 3)-8*(13 choose 4) - 28*(13 choose 5))
B = 5*(21 choose 12)+5*2*(-13-8*(13 choose 11) - 28*(13 choose 10) - (13 choose 4) - 8*(13 choose 5) - 28*(13 choose 6))
C = (21 choose 13)+2*(-1-8*13 - 28*(13 choose 11) - (13 choose 5) - 8*(13 choose 6) - 28*(13 choose 7)) 
D = 2*5*28*28+2*28*8
A/(A+B+C-D) = .723... (format works in wolfram alpha for your own web checking pleasure)

I love chopped liver, esp. at the Carnegie Deli. Yummmm... for a moment of silence. If you rule out almost anything extreme the 3-2 becomes somewhat better, how much better, that's the point of my posting.

[han]

I don't know who semeai is but he or she always seems to get these questions right.

Also agree with what semeai said about aquahombre's post, that's really wrong.

[Cyberyeti]

han, on 2011-September-22, 02:28, said:

I don't know who semeai is but he or she always seems to get these questions right.

Also agree with what semeai said about aquahombre's post, that's really wrong.

It depends, for computer dealt hands semeai is right. For hand dealt hands, the fact that your two hands are flat increases slightly the likelihood of insufficient shuffling having taken place thereby slightly increasing the odds that the other hands are flat.

[Phil]

jdeegan, on 2011-September-21, 15:32, said:

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There you see it. Odds on a 3-2 trump split. What do you think?

Sometimes my middle-aged eyes don't work so well in the morning. I thought I saw:

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What was your question again?

[mgoetze]

I suspect this question would be inadmissible in the A/E forum...

[jschafer]

Either I'm going crazy or it used to be there and got moved.