[Cyberyeti]

You're playing teams, you are in a trump contract the trump suit is as follows:

---

You can afford one trump loser but not two, W is known to hold 6 hearts to E's one, there are no ruff issues as the only possible ruff is in the heart suit, and E would be ruffing in front of your remaining Ax so ruffing a loser that isn't going anywhere with no chance W has an additional entry for a second ruff.

You are in the N hand for the first and last time at trick 1.

Run the 9 or play to the J ?

[MrAce]

Only relevant splits and their apprx % are (vacant places included, W having 7 and E having 12)

Playing to Q or J wins


KTx -- xx (6%)
KT -- xxx (4%)
Tx -- Kxx(12%)
T -- Kxxx (6%)



Playing 9 and letting it run wins

K -- Txxx(6%)
x -- KTxx (18%)
void --KTxxx (7%)

Rest of the splits seems to be push. So I would play the 9 and run it.

[Cyberyeti]

MrAce, on 2017-April-21, 07:05, said:

Only relevant splits and their apprx % are (vacant places included, W having 7 and E having 12)

Playing to Q or J wins


KTx -- xx (6%)
KT -- xxx (4%)
Tx -- Kxx(12%)
T -- Kxxx (6%)



Playing 9 and letting it run wins

K -- Txxx(6%)
x -- KTxx (18%)
void --KTxxx (7%)

Rest of the splits seems to be push. So I would play the 9 and run it.

These are not quite right, KT you have no choice but to play for the drop on the second round so you catch up if you run the 9. KTxxx is not caught by running the 9, he covers the second time and you still lose 2 tricks.

I don't normally think for long, this was one of the longest tanks of my life.

[MrAce]

Cyberyeti, on 2017-April-21, 07:18, said:

These are not quite right, KT you have no choice but to play for the drop on the second round so you catch up if you run the 9. KTxxx is not caught by running the 9, he covers the second time and you still lose 2 tricks.

You are right, this is what happens when one replies at 8 am (on my way for a black coffee)

[alok c]

Let us consider other breaks apart from 5-0. For S9 winning rho is to have K10xx,10xxx & for losing rho is to have Kxxx,Kxx,xxx,xx. For SJ winning rho is to have Kxxx,Kxx,xxx,xx & for losing rho is to have K10xx,10xxx .Other distributions are equal for both (except Kx for rho where SJ does'nt concede a trick).Though SJ wins against more combinations but S9 wins for 2nos of 4c vs 1no of 4c for SJ.In view of 6c H suit with West ,I think it is more prudent to run S9.

[Stephen Tu]

Why not just bang down the ace?

For running the 9 vs. low to the Q, the stiff T/stiff K cases on the left cancel each other out. Running the 9 picks up the KTxx onside cases but loses to the Tx/KTx offside cases, these also happen to cancel out, given the problem's vacant spaces calculation. It seems these lines are even for 4 tricks, so might as well low to the Q to pick up 5 tricks when Kx onside?

Banging down the ace picks up everything low to the Q does, + one more stiff honor offside.

[aawk]

Based on enough communication to dummy and finessing once unless the second finesse is marked and optimal defence the following situations (32 in total) are possible.

We got 3 options being playing the ace, finesse to the jack or run the 9.

holdings----------action
west-----east-----A---J---9

KT764----0--------2---2---2

KT76-----4--------2---2---2
KT74-----6--------2---2---2
KT64-----7--------2---2---2
K764-----T--------1---1---1
T764-----K--------1---1---1

KT7------64-------1---1---2
KT6------74-------1---1---2
KT4------76-------1---1---2
K76------T4-------1---1---1
K74------T6-------1---1---1
K64------T7-------1---1---1
T76------K4-------1---1---1
T74------K6-------1---1---1
T64------K7-------1---1---1
764------KT-------1---0---0

KT-------764------1---1---2
K7-------T64------1---1---1
K6-------T74------1---1---1
K4-------T76------1---1---1
T7-------K64------1---0---1
T6-------K74------1---0---1
T4-------K76------1---0---1
76-------KT4------1---0---0
74-------KT6------1---0---0
64-------KT7------1---0---0

K--------T764-----0---2---1
T--------K764-----1---0---1
7--------KT64-----2---1---1
6--------KT74-----2---1---1
4--------KT76-----2---1---1

0--------KT764----2---2---2

failing---------------8---6---9

So playing to the J only fails 6 out of 32 and therefore the best option IMHO.

You could look it up in the bridge encyclopedia but what fun is that.

[Cyberyeti]

aawk, on 2017-April-22, 01:01, said:

Based on enough communication to dummy and finessing once unless the second finesse is marked and optimal defence the following situations (32 in total) are possible.

We got 3 options being playing the ace, finesse to the jack or run the 9.

holdings----------action
west-----east-----A---J---9

KT764----0--------2---2---2

KT76-----4--------2---2---2
KT74-----6--------2---2---2
KT64-----7--------2---2---2
K764-----T--------1---1---1
T764-----K--------1---1---1

KT7------64-------1---1---2
KT6------74-------1---1---2
KT4------76-------1---1---2
K76------T4-------1---1---1
K74------T6-------1---1---1
K64------T7-------1---1---1
T76------K4-------1---1---1
T74------K6-------1---1---1
T64------K7-------1---1---1
764------KT-------1---0---0

KT-------764------1---1---2
K7-------T64------1---1---1
K6-------T74------1---1---1
K4-------T76------1---1---1
T7-------K64------1---0---1
T6-------K74------1---0---1
T4-------K76------1---0---1
76-------KT4------1---0---0
74-------KT6------1---0---0
64-------KT7------1---0---0

K--------T764-----0---2---1
T--------K764-----1---0---1
7--------KT64-----2---1---1
6--------KT74-----2---1---1
4--------KT76-----2---1---1

0--------KT764----2---2---2

failing---------------8---6---9

So playing to the J only fails 6 out of 32 and therefore the best option IMHO.

You could look it up in the bridge encyclopedia but what fun is that.

If you actually took the time to read the OP, you would see that you have extra information that says that this is absolute rubbish in this case, I wouldn't need to look it up without that.

Probabilities are skewed by the fact that W has 6 hearts to E's one, and that YOU CANNOT EVER GET BACK TO DUMMY as was clearly stated.

[Trick13]

Using http://bridge.esmarkkappel.dk/ ....


Small to the Ace is 72.96% losing only to K10xx(x) on either side.

[Joe_Old]

MrAce, on 2017-April-21, 07:05, said:

Only relevant splits and their apprx % are (vacant places included, W having 7 and E having 12)

Playing to Q or J wins


KTx -- xx (6%)
KT -- xxx (4%)
Tx -- Kxx(12%)
T -- Kxxx (6%)



Playing 9 and letting it run wins

K -- Txxx(6%)
x -- KTxx (18%)
void --KTxxx (7%)

Rest of the splits seems to be push. So I would play the 9 and run it.

Agree with Cyberyeti, plus the void -- KT764 can't be picked up if you cover the 9 with the 10. So covering either first or second round works (very small quibble).

This post has been edited by Joe_Old: 2017-April-22, 08:21

[aawk]

Cyberyeti, on 2017-April-22, 01:36, said:

If you actually took the time to read the OP, you would see that you have extra information that says that this is absolute rubbish in this case, I wouldn't need to look it up without that.

Probabilities are skewed by the fact that W has 6 hearts to E's one, and that YOU CANNOT EVER GET BACK TO DUMMY as was clearly stated.

So if I got it right this time east can trump a h if the finesse fails.

If so playing the ace is the best option to loose only 1 trick.

holdings----------action
west-----east-----A---J---9

KT764----0--------2---2---2

KT76-----4--------2---2---2
KT74-----6--------2---2---2
KT64-----7--------2---2---2
K764-----T--------1---1---1
T764-----K--------1---1---1

KT7------64-------1---2---2
KT6------74-------1---2---2
KT4------76-------1---2---2
K76------T4-------1---2---2
K74------T6-------1---2---2
K64------T7-------1---2---2
T76------K4-------1---1---2
T74------K6-------1---1---2
T64------K7-------1---1---2
764------KT-------1---0---0

KT-------764------1---2---2
K7-------T64------1---2---2
K6-------T74------1---2---2
K4-------T76------1---2---2
T7-------K64------1---1---2
T6-------K74------1---1---2
T4-------K76------1---1---2
76-------KT4------1---1---1
74-------KT6------1---1---1
64-------KT7------1---1---1

K--------T764-----1---2---1
T--------K764-----1---1---2
7--------KT64-----2---2---1
6--------KT74-----2---2---1
4--------KT76-----2---2---1

0--------KT764----2---2---2

failing---------------8---18--21

[1eyedjack]

I get the impression that you are assigning equal probability weighting to each possible holding.

[Left2Right]

Everyone, please get a free copy of a wonderful utility: SuitPlay from http://home.planet.n...cis45/suitplay/

You can tell it the card combination, the number of dummy entries, the number of unknown cards in each opponent's hand as was the question here and more.

I won't spoil it for you except to say that in this case, SuitPlay reveals that there are four different ways to play this suit in these circumstances that have a statistically equal chance to be effective (4 tricks / 72.9%)

Cheers.

[wank]

Trick13, on 2017-April-22, 02:58, said:

Using http://bridge.esmarkkappel.dk/ ....


Small to the Ace is 72.96% losing only to K10xx(x) on either side.

Nice site

[johnu]

aawk, on 2017-April-22, 08:48, said:

So if I got it right this time east can trump a h if the finesse fails.

If so playing the ace is the best option to loose only 1 trick.

The OP says that if East can ruff a heart, they are ruffing a loser so it isn't a consideration.

[ncohen]

Left2Right, on 2017-April-22, 09:22, said:

Everyone, please get a free copy of a wonderful utility: SuitPlay from http://home.planet.n...cis45/suitplay/

You can tell it the card combination, the number of dummy entries, the number of unknown cards in each opponent's hand as was the question here and more.

I won't spoil it for you except to say that in this case, SuitPlay reveals that there are four different ways to play this suit in these circumstances that have a statistically equal chance to be effective (4 tricks / 72.9%)

I don't believe that result:

I. I can only think of three lines that would be close -- run 9, to Q, and cash A. Ducking completely can't be right. Presumably, running 8 and low to J are not "different" ways.
II. Running 9 and cashing A aren't "statically equal" if you mean within a percent or so. I did it by hand, and 10x in W is about 2/3 as probable as x, and stiff 10 and K10x is about 1/3. But, 1/3 of the chance of stiff X in W is statistically significant.

[1eyedjack]

Deleted rubbish

[msjennifer]

I am poor at the mathematics.However, as a simpleton,On the table,I would not like to concede an unnecessary trick to a singleton or doubleton 10 with my LHO and so I will play small to the jack all the time.

[msjennifer]

I am poor at the mathematics.However, as a simpleton,On the table,I would not like to concede an unnecessary trick to a singleton or doubleton 10 with my LHO and so I will play small to the jack all the time.

[Cyberyeti]

I sat and thought for about 3 minutes trying to calculate, realised it was really close at the table, successfully ran the 9 (K10xx onside) for a swing, the other declarer played small to the J.