BBO Discussion Forums: For probability experts - BBO Discussion Forums

Jump to content

Page 1 of 1
  • You cannot start a new topic
  • You cannot reply to this topic

For probability experts

#1 User is offline   mikeh 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 13,085
  • Joined: 2005-June-15
  • Gender:Male
  • Location:Canada
  • Interests:Bridge, golf, wine (red), cooking, reading eclectically but insatiably, travelling, making bad posts.

Posted 2024-October-26, 19:37



The bidding is no thing of beauty, but as they say, the play’s the thing.

2S was 9+ to 13-, 6 card suit. 3D was showing a good hand with hearts, 3S denied a fit and 4S was optimistic…but I’d usually have a better hand and this is imps. Plus we’d clawed back from 20th out of 24 to lie 14th and needed to build a cushion since our last day will include matches against the two top teams.

Ok…a club lead and there’s no story nor any problem. But I got a diamond lead.

So…plan the play.

To me, I thought I had two options.

1. win in hand, hook the heart.if it wins, hope to pitch both clubs. Obviously, if it loses, I’m down multiple undertricks.

2. cash two hearts immediately, pitching 1 club and hope to play spades for two losers.

To make it a little more testing…there are strict time limits and slow play attracts VP penalties, which we couldn’t really afford.


Ok…your line and why.

I did choose one of those options but I don’t know whether my choice was the theoretically correct one.I think it fascinating, but I’m a bit weird that way😀
'one of the great markers of the advance of human kindness is the howls you will hear from the Men of God' Johann Hari
1

#2 User is offline   jillybean 

  • hooked
  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 10,311
  • Joined: 2003-November-15
  • Gender:Female
  • Location:Vancouver, Canada
  • Interests:Multi

Posted 2024-October-26, 20:07

Your spade suit is pitiful, I am going for the heart hook.
"And no matter what methods you play, it is essential, for anyone aspiring to learn to be a good player, to learn the importance of bidding shape properly." MikeH
0

#3 User is offline   Stephen Tu 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 4,101
  • Joined: 2003-May-14

Posted 2024-October-27, 08:19

I think the heart hook is almost certainly best. In a vacuum, picking up the spades is like 51.67%. Which is marginally better than a hook. But on this hand, trying to play spades for 2 losers will involve losing a spade, then maybe a club & a possible diamond ruff for an extra spade loser, which should kill that edge.
0

#4 User is offline   mikeh 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 13,085
  • Joined: 2005-June-15
  • Gender:Male
  • Location:Canada
  • Interests:Bridge, golf, wine (red), cooking, reading eclectically but insatiably, travelling, making bad posts.

Posted 2024-October-27, 14:31

View PostStephen Tu, on 2024-October-27, 08:19, said:

I think the heart hook is almost certainly best. In a vacuum, picking up the spades is like 51.67%. Which is marginally better than a hook. But on this hand, trying to play spades for 2 losers will involve losing a spade, then maybe a club & a possible diamond ruff for an extra spade loser, which should kill that edge.

While at imps one always tries to make, the two lines aren’t about making or going down one. If the heart hook loses, you are down two virtually no matter what. If you think, as I do, that game is likely to be missed at the other table, -100 v +110 is 5 imps while -50 is only 4 imps. Given that this is a nv game, that 1 imp may…I don’t say should always…be a factor to consider when the odds either way are as close as I think they are.

Plus, while unlikely, if hearts are 5=2 and the short hearts have short spades, the heart hook doesn’t gain even when it wins! So I don’t think it’s as simple as it may initially appear. Indeed, I doubt that even a Rodwell or Rosenberg would be entirely sure of the percentages at the table.

I played on spades…everything works and I could have scored an overtrick. They (properly, imo) ‘missed’ the game at the other table
'one of the great markers of the advance of human kindness is the howls you will hear from the Men of God' Johann Hari
0

#5 User is offline   Stephen Tu 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 4,101
  • Joined: 2003-May-14

Posted 2024-October-27, 15:52

View Postmikeh, on 2024-October-27, 14:31, said:

While at imps one always tries to make, the two lines aren't about making or going down one. If the heart hook loses, you are down two virtually no matter what. If you think, as I do, that game is likely to be missed at the other table, -100 v +110 is 5 imps while -50 is only 4 imps. Given that this is a nv game, that 1 imp may…I don't say should always…be a factor to consider when the odds either way are as close as I think they are.

Plus, while unlikely, if hearts are 5=2 and the short hearts have short spades, the heart hook doesn't gain even when it wins! So I don't think it's as simple as it may initially appear. Indeed, I doubt that even a Rodwell or Rosenberg would be entirely sure of the percentages at the table.


I don't agree with the latter part of your analysis. Say qx of hearts was onside, and North has the doubleton spade and ruffs when you play the third heart and pitch second club loser. You can still get out for just two additional trump losers if the ruff was from KQ, KT, QT, K8, Q8, T8. For some of the combos that you are going to lose to, like Kx/qx, line 2 fails also. Similar if hearts are 5-2 and 2 spades onside, you still pick up some combos, and of the ones that fail, many were also losses for line 2.

I think the making odds for heart hook are substantially higher. Would I be able to calculate exactly at the table, certainly not. But my gut says it's substantially better, not a close to tossup. By enough to ignore the extra imp of going down extra I believe.
0

#6 User is offline   hrothgar 

  • PipPipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 15,497
  • Joined: 2003-February-13
  • Gender:Male
  • Location:Natick, MA
  • Interests:Travel
    Cooking
    Brewing
    Hiking

Posted 2024-October-27, 18:24

View PostStephen Tu, on 2024-October-27, 08:19, said:

I think the heart hook is almost certainly best. In a vacuum, picking up the spades is like 51.67%. Which is marginally better than a hook. But on this hand, trying to play spades for 2 losers will involve losing a spade, then maybe a club & a possible diamond ruff for an extra spade loser, which should kill that edge.


My concern is also the possibility of a Diamond ruff
Alderaan delenda est
0

#7 User is offline   thepossum 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,594
  • Joined: 2018-July-04
  • Gender:Male
  • Location:Australia

Posted 2024-October-28, 06:05

Sorry for following this. Thought it may be a probability question
But I am struggling to see game at all. I have 9 tricks if I am lucky
What is the assumption of everyone else's contract?
I am paying the poster considerable respect of applying my very intermediate brain to the hand for a long time to work out how to play it
I do think given the lack of apparent tricks I would possibly consider the heart finesse while you had the chance
3 heart tricks, knock out your club losers, finesse a spade, before or after a few rounds of diamonds and then hope
Probability is close to zero for me
0

#8 User is offline   nullve 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,326
  • Joined: 2014-April-08
  • Gender:Male
  • Location:Norway
  • Interests:partscores

Posted 2024-October-28, 17:51

View Postmikeh, on 2024-October-26, 19:37, said:

But I got a diamond lead.

Can you be more specific?
0

#9 User is offline   gszes 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,664
  • Joined: 2011-February-12

Posted 2024-November-26, 22:07

There appears to be so many ways to lose 3 spades that I would feel compelled to try the heart finesse.
0

#10 User is offline   thepossum 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,594
  • Joined: 2018-July-04
  • Gender:Male
  • Location:Australia

Posted 2024-December-05, 04:55

I keep reading this thread looking for expert statistical discussion
0

Page 1 of 1
  • You cannot start a new topic
  • You cannot reply to this topic

2 User(s) are reading this topic
0 members, 2 guests, 0 anonymous users