Simple play problem
rich
West Dealer
Good Junior opponents
3C* P P 4H
all pass
*weak
KQ75
2
K9432
763
8
AKQT95
AQT5
84
Opening Lead Jd, K, 8, 10 (8 is udca)
H2, 8, ?
Rich Regan
TWOferBRIDGE
88888888888888888888888888888888888888
Close to a toss up between hook or drop
if my math is right.
Hook for the J is 50% ( either LHO has it or he doesn't )
Dropping is ~ 51.6%
- - Don - -
3-3 splt = 35.5 %
4-2 split = 48.4 % and J x doubleton
occurs 2/6 of 48.4 = 16.1 % .
So 16.1 + 35.5 = 51.6 %
Richard Pavlicek
Many years ago I learned that regardless of the available-space
ratio the best play for six tricks (no loser) is to cash the tops.
One might think this would change with RHO more likely to be long,
but it doesn't; essentially because the finesse only gains against
jack-fourth (not jack-fifth) while losing to J, Jx or Jxx.
--
Richard Pavlicek
Web site: http://www.rpbridge.net
Stu Goodgold
The DJ lead looks like a singleton, reinforced by East's D8,
presumably count from 876. It is only wrong to go up with the HA if
West also has a small singleton heart. I would pay off to the
unlikely West distribution of 4-1-1-7, since he opened 3C in first
seat.
Moreover, if you do finesse and it loses, you will surely go down 2,
and maybe 3, West doesn't have both CA and CK, so he will cash one
and continue the suit, then get a ruff. (or East has the stiff CA and
will give an immediate ruff). Spade to East's A and then perhaps
another diamond ruff.
-Stu Goodgold
San Jose, CA
rich
>
> - Show quoted text -
Thank you. I played the 10H, I now see my error.
RR
boblipton
You neglected the chance of the 5-1 split with the stiff Jack. Of
course, when you lead the first trump off the board and the Jack
doesn't pop out, you've cut the chance in half, but it still adds 1.2%
to your chances.
In addition, there are neutral positions that should be excluded from
the calculation i.e., cases where lefty has four trumps to the jack
and it doesn't matter. That pushes the odds in favor of the drop a
touch higher.
Bob
rhm
Does this mean that you can mathematically prove that regardless how
skewed the available spaces are J, Jx , Jxx on your left is more
likely than Jxxx on your right?
Say West has 3 unknown cards, while East has 13.
Is it still right to play from the top?
I checked this with your Hand Pattern Analyzer and gave West 8 clubs
and 2 diamonds and if I calculated correctly there was a slight
advantage playing for the finesse.
Rainer Herrmann
Richard Pavlicek
> On Aug 29, 8:59 pm, "Richard Pavlicek" <rich...@rpbridge.net> wrote:
>> Rich Regan asked:
>> Imps pairs, All White
>> West Dealer
>> Good Junior opponents
>>
>> 3C* P P 4H
>> all pass
>> *weak
>>
>> KQ75
>> 2
>> K9432
>> 763
>>
>> 8
>> AKQT95
>> AQT5
>> 84
>>
>> Opening Lead Jd, K, 8, 10 (8 is udca)
>> H2, 8, ?
>>
>> Many years ago I learned that regardless of the available-space
>> ratio the best play for six tricks (no loser) is to cash the tops.
>> one might think this would change with RHO more likely to be long,
>> but it doesn't; essentially because the finesse only gains against
>> jack-fourth (not jack-fifth) while losing to J, Jx or Jxx.
>
> Does this mean that you can mathematically prove that regardless how
> skewed the available spaces are J, Jx, Jxx on your left is more
> likely than Jxxx on your right?
> Say West has 3 unknown cards, while East has 13.
> Is it still right to play from the top?
No, "regardless" was an overbid. The advice was general for any
situation likely to occur in practice. Doing some checking shows
that if another suit is known to divide 8-1 (5:12 spaces), it is
still right to cash AKQ; but if 9-1 (4:12 spaces), the finesse is
slightly better.
Oh, and my "mathematical proofs" are never wasted on bridge but
reserved for important things... like the volume of a pizza with
altitude 'a' and radius 'z' = pizza.
Dave Flower
I have carried out a bean-counting exercise, looking at all possible
hands. I assumed:
1) Clubs are 7-1
2) East holds SA
3) West started with DJ, DJ7 or DJ6
4) West was not 2-1 in spades and diamonds
5) With equal length in spades and diamonds, West would lead a diamond
half the time.
Under thse assumptions, finessing makes 44.5% and playing for the drop
52.5%
If I further assume that West does not hold a 4-card major, these
figures become 53.2% and 68.4% respectively
Playing for the drop appears clear cut
Dave Flower
Steve Willner
> Rich Regan asked:
>
>> Imps pairs, All White
>> West Dealer
>> Good Junior opponents
>>
>> 3C* P P 4H
>> all pass
>> *weak
>>
>> KQ75
>> 2
>> K9432
>> 763
>>
>> 8
>> AKQT95
>> AQT5
>> 84
>>
>> Opening Lead Jd, K, 8, 10 (8 is udca)
>> H2, 8, ?
>
> Many years ago I learned that regardless of the available-space
> ratio the best play for six tricks (no loser) is to cash the tops.
Let me see if I have this right: finessing loses a makeable contract if
West has J (one case), Jx (five cases), or Jxx (ten cases) for a total
of 16 cases. Playing for the drop loses only to xx (ten cases). So the
finesse is right only if the available space ratio is so skewed that Jxx
is wildly unlikely.
If the hands were rearranged so the finesse could be taken twice (or a
trump coup would work), declarer could pick up a small singleton (five
cases) in West. Then it becomes attractive to finesse whenever Jxx has
diminished likelihood relative to xx, not only when it's a rare event.
--
Help keep our newsgroup healthy; please don't feed the trolls.
Steve Willner Phone 617-495-7123 swil...@cfa.harvard.edu
Cambridge, MA 02138 USA
Charles Brenner
nicely put.