BBO Discussion Forums: Bidding Challenge: very difficult to get slam on competition - BBO Discussion Forums

Jump to content

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

Bidding Challenge: very difficult to get slam on competition

#1 User is offline   lycier 

  • PipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 7,612
  • Joined: 2009-September-28
  • Gender:Male
  • Location:China

Posted 2015-December-20, 18:11

Today I looked on TM at BBO,players are bbo star,the hand at below:





West second double may be not good,however I found it is very very difficult to get slam on competition,very impossible to find 7.

This is a bidding challenge.
Playing 2/1
Normally it goes :


Now I am very curious to know whether both of you and your partner have ability to get slam on competition.
Any challenger is welcomed.
0

#2 User is offline   Cyberyeti 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 13,934
  • Joined: 2009-July-13
  • Location:England

Posted 2015-December-20, 19:24

You don't want to find 7 without the Q, you do want to find 6 and 6 is better than the 6 I think I'd reach.
0

#3 User is offline   wank 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,866
  • Joined: 2008-July-13

Posted 2015-December-21, 07:40

lol west is on crack.
0

#4 User is offline   Lovera 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,723
  • Joined: 2014-January-12
  • Gender:Male
  • Location:Bari (ITALIA)
  • Interests:I'm also on YOUTUBE with a channel of music songs .

Posted 2015-December-21, 11:56

Why ? After 4 S bids 5 as RKB(h) and N doesn't consider club void(=not usefull). The answer of 5 meaning, yet with 7th plus two support cards by partner in trump can be considered that is, 2 keys plus (much presumible inside) Queen and with 5(=all six keys) it is indicate the diamond King for seven. South needs partner had almost 19 points for to try to investigate for slam.
0

#5 User is offline   manudude03 

  • - - A AKQJT9876543
  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,610
  • Joined: 2007-October-02
  • Gender:Male

Posted 2015-December-21, 12:45

View PostLovera, on 2015-December-21, 11:56, said:

Why ? After 4 S bids 5 as RKB(h) and N doesn't consider club void(=not usefull). The answer of 5 meaning, yet with 7th plus two support cards by partner in trump can be considered that is, 2 keys plus (much presumible inside) Queen and with 5(=all six keys) it is indicate the diamond King for seven. South needs partner had almost 19 points for to try to investigate for slam.


The seventh heart isn't enough to justify lying about the queen. Here, you are a priori about 53% to pick up trumps without loss, and even then you go off with a 4-0 diamond break. Horrible odds for a grand when there is a very real chance the other tables won't even reach 6.
Wayne Somerville
0

#6 User is offline   Lovera 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,723
  • Joined: 2014-January-12
  • Gender:Male
  • Location:Bari (ITALIA)
  • Interests:I'm also on YOUTUBE with a channel of music songs .

Posted 2015-December-21, 12:58

Sorry, my mistake because we not have all the keys. But if N consider void like an Ace bidding 5 querying with 5 for Q is indicated(=yes Q) the diamond King with the answer of 6 ...
0

#7 User is offline   Lovera 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,723
  • Joined: 2014-January-12
  • Gender:Male
  • Location:Bari (ITALIA)
  • Interests:I'm also on YOUTUBE with a channel of music songs .

Posted 2015-December-21, 13:06

View Postmanudude03, on 2015-December-21, 12:45, said:

The seventh heart isn't enough to justify lying about the queen. Here, you are a priori about 53% to pick up trumps without loss, and even then you go off with a 4-0 diamond break. Horrible odds for a grand when there is a very real chance the other tables won't even reach 6.

I'm on going to variate the ten card sureing presence of Q(=fall) as equal at nine with Q inside(=under impasse) that much probably is having opp doubled. Although if you are right about "Horrible odds.." than the bidding problem there is not.
0

#8 User is offline   manudude03 

  • - - A AKQJT9876543
  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,610
  • Joined: 2007-October-02
  • Gender:Male

Posted 2015-December-21, 16:28

View PostLovera, on 2015-December-21, 13:06, said:

I'm on going to variate the ten card sureing presence of Q(=fall) as equal at nine with Q inside(=under impasse) that much probably is having opp doubled. Although if you are right about "Horrible odds.." than the bidding problem there is not.


The reason you can lie when you have a 10 card fit is that if you don't possess the jack, you have a 78% chance of playing the suit without loss. If you have the jack, it goes up to 89%. Considerably more likely than the 53% chance when it is only a 9 card fit.
Wayne Somerville
0

#9 User is offline   Cyberyeti 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 13,934
  • Joined: 2009-July-13
  • Location:England

Posted 2015-December-21, 17:57

View Postmanudude03, on 2015-December-21, 12:45, said:

The seventh heart isn't enough to justify lying about the queen. Here, you are a priori about 53% to pick up trumps without loss, and even then you go off with a 4-0 diamond break. Horrible odds for a grand when there is a very real chance the other tables won't even reach 6.


If you're going to play a grand, you're better in diamonds, you can survive the hearts 3-1 if diamonds are 2-2.

The small slam is better in hearts as a spade lead is awkward in 6 if both reds are 3-1 whereas 6 is cold.
0

#10 User is offline   Lovera 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,723
  • Joined: 2014-January-12
  • Gender:Male
  • Location:Bari (ITALIA)
  • Interests:I'm also on YOUTUBE with a channel of music songs .

Posted 2015-December-22, 10:01

View Postmanudude03, on 2015-December-21, 16:28, said:

The reason you can lie when you have a 10 card fit is that if you don't possess the jack, you have a 78% chance of playing the suit without loss. If you have the jack, it goes up to 89%. Considerably more likely than the 53% chance when it is only a 9 card fit.

Apart the fact that when there is a double the planning is oriented, i want report what Guido Barbone (ex CNP for our Blue Team and President of FIGB) wrote in his book "Il libro completo del bridge di gara" about The contracts of grand slam: ".. In the racing bridge however, it is sufficient that the odds are favorable by approximately 60% to qualify rational any declaration of a grand slam. The more liberal attitude is explained by the fact that in a tournament almost the entire hall declares a grand slam to 70% and that, consequently, the good player should not risk a little more than on the distance, it ends up producing positive resulting . The suggest ..becomes from the findings made by examining the modules score pairs competition of great importance: the strong pairs tend to declare big slam that also offer only 55% of the odds favoureble. .." (pagg. 129-130).
0

#11 User is offline   manudude03 

  • - - A AKQJT9876543
  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,610
  • Joined: 2007-October-02
  • Gender:Male

Posted 2015-December-22, 15:49

View PostLovera, on 2015-December-22, 10:01, said:

Apart the fact that when there is a double the planning is oriented, i want report what Guido Barbone (ex CNP for our Blue Team and President of FIGB) wrote in his book "Il libro completo del bridge di gara" about The contracts of grand slam: ".. In the racing bridge however, it is sufficient that the odds are favorable by approximately 60% to qualify rational any declaration of a grand slam. The more liberal attitude is explained by the fact that in a tournament almost the entire hall declares a grand slam to 70% and that, consequently, the good player should not risk a little more than on the distance, it ends up producing positive resulting . The suggest ..becomes from the findings made by examining the modules score pairs competition of great importance: the strong pairs tend to declare big slam that also offer only 55% of the odds favoureble. .." (pagg. 129-130).


The 55% there assumes the field will always be in at least 6. Here you have 11 HCP opposite 10 HCP, hardly trivial to even get to the small slam, so you need to be pretty sure it is making before you bid it.
Wayne Somerville
0

#12 User is offline   Lovera 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,723
  • Joined: 2014-January-12
  • Gender:Male
  • Location:Bari (ITALIA)
  • Interests:I'm also on YOUTUBE with a channel of music songs .

Posted 2015-December-22, 17:17

And the author continues so always talking about grand slam contracts (..=):"For this reason a grand slam to 60%, if ends negatively yet , it is not a zero because who bidded it he finds himself in good company and a company the more numerous the more fierce is the field of the participants in that tournament . Conversely, if slam is feasible, those who do not declare their lost valuable points against the most formidable competitors. It is clear, however, that if the level of play of the room is quite poor reasoning does not apply."
0

#13 User is offline   manudude03 

  • - - A AKQJT9876543
  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,610
  • Joined: 2007-October-02
  • Gender:Male

Posted 2015-December-22, 17:45

I think you overestimate the field a lot. I would say that even in the finals of the Bermuda Bowl, a hand like this would be a very likely big swing if you were to bid and make a grand here. Maybe someone with actual BB experience would correct me :P
Wayne Somerville
0

#14 User is offline   Lovera 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,723
  • Joined: 2014-January-12
  • Gender:Male
  • Location:Bari (ITALIA)
  • Interests:I'm also on YOUTUBE with a channel of music songs .

Posted 2015-December-22, 18:26

View Postmanudude03, on 2015-December-22, 17:45, said:

I think you overestimate the field a lot. I would say that even in the finals of the Bermuda Bowl, a hand like this would be a very likely big swing if you were to bid and make a grand here. Maybe someone with actual BB experience would correct me :P

If you are spoking about percentage or chance than we are agree :55 or 53 are similar.
0

#15 User is offline   PhilKing 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,240
  • Joined: 2012-June-25

Posted 2015-December-22, 19:09

Bidding a borderline grand slam is bonkers if it is unlikely that slam will be reached elsewhere.
0

#16 User is offline   Cyberyeti 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 13,934
  • Joined: 2009-July-13
  • Location:England

Posted 2015-December-22, 19:56

View PostPhilKing, on 2015-December-22, 19:09, said:

Bidding a borderline grand slam is bonkers if it is unlikely that slam will be reached elsewhere.


Indeed, even though 7 is about 70% (diamonds 2-2 can deal with any heart position not involving a trick 1 ruff, diamonds 3-1 you have the same 52% chance that 7 has and this assumes they lead a spade, on a club lead it's cold barring diamonds 4-0) it's still against the odds to bid it as you rate to cash in for most of the gain by just bidding 6.
0

#17 User is offline   manudude03 

  • - - A AKQJT9876543
  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,610
  • Joined: 2007-October-02
  • Gender:Male

Posted 2015-December-23, 01:07

View PostPhilKing, on 2015-December-22, 19:09, said:

Bidding a borderline grand slam is bonkers if it is unlikely that slam will be reached elsewhere.


Indeed, if we assume that the other table land in 4H (assuming nv) and slam is one off undoubled if not making:
6D: +10 if it makes, -11 if it goes off. (52.4% chance for break even*)
6H: +11 if it makes, -11 if it goes off. (50% chance for break even*)
7D/H: +14 if it makes, -11 if it goes off. (44% chance for break even*)

* if your only options were playing 4H, or that particular slam.

However, it is very wrong to think that the 44% chance for break even for 7H/S is right. If we are always bidding at least 6 (and the other table is playing 4H), then are gaining an extra 3 imps (assuming we were always playing in 6H if any small slam) if it makes 13 tricks, but losing 22 if there are only 12 tricks, that makes our break even point when deciding between 6 and 7 at 92% i.e You must be pretty damn near certain it is making.
Wayne Somerville
0

#18 User is offline   Lovera 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,723
  • Joined: 2014-January-12
  • Gender:Male
  • Location:Bari (ITALIA)
  • Interests:I'm also on YOUTUBE with a channel of music songs .

Posted 2015-December-24, 03:03

Although this seems another situation where all fit to solve at double dummy: here with K we can have 13 tricks. Infact another sequence may be ..(4)-4NT, (p)-5NT(=2 keys+Q as told+void) and after 6(=? for void)-7. But because we have not had notice in bidding if void instead is in diamond we have to play against 6-1-2-4 stiff Q of trump to estabilish Q and King of club third in dummy(=A to expasse) for 12 tricks.
0

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

1 User(s) are reading this topic
0 members, 1 guests, 0 anonymous users