BBO Discussion Forums: atb - BBO Discussion Forums

Jump to content

  • 2 Pages +
  • 1
  • 2
  • You cannot start a new topic
  • You cannot reply to this topic

atb

#1 User is offline   wank 

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

Posted 2014-June-09, 05:57



-1100 when opps were one off in 5h. atb. i was asked my opinion on this hand and was told i was talking out of my arse. (why ask if you don't listen?) these players will be playing the open europeans in 2 weeks.

Q) What was the arrangement for the 2N ? split range ? A) Anything from kqxxx aqxxx with nothing outside upwards.

i was east at this table btw. amusing situation around this match. this was a 64 board final after a qualifying league and we had a +22 imp carryover. we sold our 22 imps back to the opps on condition they agreed to play winner-takes-all for the prize money (it was almost as good for 2nd as for winning). first set we lost 4. second set we lost 21. third set we lost 10. it wasn't looking like a terribly good investment. in the fourth set we picked up 36 to win by an imp. prizes were 1600 for first and 1200 for second (dodgy local currency so don't be impressed). someone who's good at maths can tell me what our imps/board expectation would need to be to make this an attractive deal. i suppose it's hard to estimate the standard deviation though.
0

#2 User is offline   Cyberyeti 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 13,949
  • Joined: 2009-July-13
  • Location:England

Posted 2014-June-09, 06:12

What was the arrangement for the 2N ? split range ?
0

#3 User is offline   Fluffy 

  • World International Master without a clue
  • PipPipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 17,404
  • Joined: 2003-November-13
  • Gender:Male
  • Location:madrid

Posted 2014-June-09, 06:21

certainly 1100 was more than they deserved. One can codify south's bidding at this vulnerability to tell the table if he is bidding with confidence or not, but this could backfire often so probably not worth it.

I think north bid his hand twice, south is wide ranged since he is under pressure. North is going 500 against nothing too often, making 6 is certainly possible, but its looking for the miracle hand.

South traded -420 for -800 opposite a very big hand, so probably deserves some blame as well, but he had put pressure on the opps to get 850 back so he has a point.
0

#4 User is offline   P_Marlowe 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 10,084
  • Joined: 2005-March-18
  • Gender:Male

Posted 2014-June-09, 06:25

Hi,

the question is, did North bid 6C to make?

I dont think so. He cant know, that one of his spade loosers got covered,
and South never promised the Ace of diamonds, so he was sacrificing against
5H. And sacrificing red against green is a huge proposition.

In the end it comes down, what does a red vs. green 2NT promise, the North
hand is certainly a supermax, but that is it.

With kind regards
Marlowe
With kind regards
Uwe Gebhardt (P_Marlowe)
1

#5 User is offline   billw55 

  • enigmatic
  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 4,757
  • Joined: 2009-July-31
  • Gender:Male

Posted 2014-June-09, 06:27

IMO once north chooses 2NT he should leave decisions to partner, whose hand is totally unknown.

Personally, I think I would choose 2 with the north hand.
Life is long and beautiful, if bad things happen, good things will follow.
-gwnn
0

#6 User is offline   helene_t 

  • The Abbess
  • PipPipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 17,099
  • Joined: 2004-April-22
  • Gender:Female
  • Location:UK

Posted 2014-June-09, 06:34

It may be a good discussion if U2NT works like a preempt, i.e. overcaller can never bid on his own but at most double to suggest a sac. Otherwise I have sympathy with North. A forward double by North would work great here.

South has a difficult decision. A DSIP double would be great but presumably it is penalties. I suppose I would have bid 5 myself.

There is a lot of bad luck on this board, though.
The world would be such a happy place, if only everyone played Acol :) --- TramTicket
0

#7 User is offline   gszes 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,656
  • Joined: 2011-February-12

Posted 2014-June-09, 07:18

norths decision to bid 6c seems very reasonable since
down 1 is a very reasonable probability and making is
not an outlandish concept. 2N at these colors is very
reasonable and having a tad extra in reserve is hardly
a horrific thing.

ATB 100% south

I am having trouble trying to imagine what kind of hand south
was hoping for when they bid 5c. South had to realize the
spade KQ were virtually certain to be useless on offense, so
that means they are bringing 1 trick (heart A) and a possibly
useless club Q (IF they have a 10 card fit). Did south really
expect the north hand to be worth ten tricks and if so why
would N ever stop at the 5 level? Just far too many questions
at these colors where overbidding can turn disastrous quickly.
0

#8 User is offline   Fluffy 

  • World International Master without a clue
  • PipPipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 17,404
  • Joined: 2003-November-13
  • Gender:Male
  • Location:madrid

Posted 2014-June-09, 08:16

I forgot, if bidding on, north should rather double than bid 6
1

#9 User is offline   hotShot 

  • Axxx Axx Axx Axx
  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,976
  • Joined: 2003-August-31
  • Gender:Male

Posted 2014-June-09, 08:25

I don't see much blame to assign here.

North definitely has his 2NT bid.
He can Assume that South bid 5 to make it or because he was sure that 4 will make and 5 is not more than 2 down.
The South hand is hard to evaluate, the 2 tricks in the majors might be unneeded as North is short there.
No honors in and just the Q could mean that top tricks in these suits might be lost.

But the South hand is strong enough to try 5.

The biggets portion of blame goes to bad luck.
0

#10 User is offline   ahydra 

  • AQT92 AQ --- QJ6532
  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,840
  • Joined: 2009-September-09
  • Gender:Male
  • Location:Wellington, NZ

Posted 2014-June-09, 09:15

How did this manage to go for 1100? Did East have DAxx and a singleton SA or something? Pretty unlucky.

South hand looks very defensive, I'm not sure I would try 5C, that might already be down 500 let alone what will happen if partner bids on with a good hand as he did here. Still you have a double-fit and HA so I guess you need to do something - depends if you have good agreements about X. If I have to blame anyone it's South but to be honest this is more bad luck than bad judgement.

ahydra
0

#11 User is offline   billw55 

  • enigmatic
  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 4,757
  • Joined: 2009-July-31
  • Gender:Male

Posted 2014-June-09, 09:47

View Postahydra, on 2014-June-09, 09:15, said:

How did this manage to go for 1100? Did East have DAxx and a singleton SA or something? Pretty unlucky.

South hand looks very defensive, I'm not sure I would try 5C, that might already be down 500 let alone what will happen if partner bids on with a good hand as he did here. Still you have a double-fit and HA so I guess you need to do something - depends if you have good agreements about X. If I have to blame anyone it's South but to be honest this is more bad luck than bad judgement.

ahydra

I am assuming A, ruff, A, ruff, ruff. Yeah, pretty unlucky.

I like 5. South holds a double fit and controls in both side suits. The upside is a vulnerable game, while the likely downside of -500 vs. -420 is not a huge disaster. Maybe that's why I'm not an expert.
Life is long and beautiful, if bad things happen, good things will follow.
-gwnn
0

#12 User is offline   Cyberyeti 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 13,949
  • Joined: 2009-July-13
  • Location:England

Posted 2014-June-09, 10:04

View Postahydra, on 2014-June-09, 09:15, said:

How did this manage to go for 1100? Did East have DAxx and a singleton SA or something? Pretty unlucky.

South hand looks very defensive, I'm not sure I would try 5C, that might already be down 500 let alone what will happen if partner bids on with a good hand as he did here. Still you have a double-fit and HA so I guess you need to do something - depends if you have good agreements about X. If I have to blame anyone it's South but to be honest this is more bad luck than bad judgement.

ahydra


I presume W had something like AJxxxx, xxxx, A, xx as that's the only way I can see 5 going off, it's not impossible W could have held AJxxxx, 98xx, Axx, void where 5 was potentially making an overtrick.

If 2N is split range, S has bid 5 opposite a much weaker hand than that so bidding 6 is routine with the N hand, S might have held a similar hand with A instead of A and a spade less.

S therefore is where any blame would lie. Do you want to bid 5 opposite a typical 2N bid ? that depends what a typical 2N bid looks like for you at this vul. Say xx, x, KQ9xx, KJ10xx, this is 3 losers if you avoid a second diamond loser and they can't engineer a spade or diamond ruff, but then they might not be able to make 4. So I'd lay the blame there, even KQJxx is no bargain and can dial a big number.
0

#13 User is offline   WellSpyder 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,627
  • Joined: 2009-November-30
  • Location:Oxfordshire, England

Posted 2014-June-09, 10:24

I blame East for doubling....
0

#14 User is offline   FrancesHinden 

  • Limit bidder
  • PipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 8,482
  • Joined: 2004-November-02
  • Gender:Female
  • Location:England
  • Interests:Bridge, classical music, skiing... but I spend more time earning a living than doing any of those

Posted 2014-June-09, 12:43

I think this is a joint effort.

I don't like South's 5C bid: 10xx in diamonds is a poor holding not a good one and the spade honours are defensive. There's no indication partner is short in hearts - it's not as if the opponents have had a fit auction. If partner has, say, - xx KQxxx Axxxxx that strikes me as a perfectly good 2NT bid opposite which 5C is at least one off and 4H hasn't actually made yet.

I also don't like North's 6C bid. If he's going to act, he should double to show extras. He's actually got no idea what South had to bid 5C.

(This raises the point about what 4S and 4NT should mean by South. We don't pay 2NT as unusual, but in the equivalent auction we would say 4S is a good 5C bid, 4NT is a good 5D bid and 5m is a save)
1

#15 User is offline   FrancesHinden 

  • Limit bidder
  • PipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 8,482
  • Joined: 2004-November-02
  • Gender:Female
  • Location:England
  • Interests:Bridge, classical music, skiing... but I spend more time earning a living than doing any of those

Posted 2014-June-09, 12:52

View Postwank, on 2014-June-09, 05:57, said:


We sold our 22 imps back to the opps on condition they agreed to play winner-takes-all for the prize money (it was almost as good for 2nd as for winning). first set we lost 4. second set we lost 21. third set we lost 10. it wasn't looking like a terribly good investment. in the fourth set we picked up 36 to win by an imp. prizes were 1600 for first and 1200 for second (dodgy local currency so don't be impressed). someone who's good at maths can tell me what our imps/board expectation would need to be to make this an attractive deal. i suppose it's hard to estimate the standard deviation though.



Not sure what you mean by 'sold' - did they pay you for the 22 imps, or did you simply give them back in exchange for winner-takes-all?

If the latter than you were swapping +22 imps for 1600 or 1200 DLCs vs 0 imps for 2800 or 0 DLCs.

Maybe I'm missing the point, but if your utility function is completely straight (every additional DLC more or less is worth the same to you), this doesn't seem like a difficult maths problem: it's a good deal if you expect to win by 23 imps or more, and a bad deal if you don't.

The standard deviation is only relevant if your utility function isn't straight.
0

#16 User is offline   whereagles 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 14,900
  • Joined: 2004-May-11
  • Gender:Male
  • Location:Portugal
  • Interests:Everything!

Posted 2014-June-09, 13:09

Maybe 5 was optimistic, maybe 6 was a stretch, but both actions seem normal.

The -1100 was quite unlucky. -800, or even -500, is more normal.
0

#17 User is offline   MickyB 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,290
  • Joined: 2004-May-03
  • Gender:Male
  • Location:London, England

Posted 2014-June-09, 13:21

I agree with Frances on the bridge, but not on the maths. How many imps you expect to win by is irrelevant, it's your win percentage that matters.

Your expectancy, pre-deal, will have been around 1500 DLCs. You only need to win 53.6% of the time to have an expectancy of 1500 DLCs post-deal.

Based on this data, you would need to be better by about 0.07 imps per board to make the deal breakeven.

Plugging the pre-deal numbers back in [carryover plus superiority giving you a 26.2 imp advantage over 60 boards] is roughly in line with the initial assumption of a 75% winrate/1500 DLC expectancy, so these numbers look about right to me.
1

#18 User is offline   the hog 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 10,728
  • Joined: 2003-March-07
  • Gender:Male
  • Location:Laos
  • Interests:Wagner and Bridge

Posted 2014-June-09, 15:06

View Postwank, on 2014-June-09, 05:57, said:



-1100 when opps were one off in 5h. atb. i was asked my opinion on this hand and was told i was talking out of my arse. (why ask if you don't listen?) these players will be playing the open europeans in 2 weeks.

Q) What was the arrangement for the 2N ? split range ? A) Anything from kqxxx aqxxx with nothing outside upwards.

i was east at this table btw. amusing situation around this match. this was a 64 board final after a qualifying league and we had a +22 imp carryover. we sold our 22 imps back to the opps on condition they agreed to play winner-takes-all for the prize money (it was almost as good for 2nd as for winning). first set we lost 4. second set we lost 21. third set we lost 10. it wasn't looking like a terribly good investment. in the fourth set we picked up 36 to win by an imp. prizes were 1600 for first and 1200 for second (dodgy local currency so don't be impressed). someone who's good at maths can tell me what our imps/board expectation would need to be to make this an attractive deal. i suppose it's hard to estimate the standard deviation though.


North is to blame. Bid your hand once and then don't bid again. North violated this rule and paid the price.
"The King of Hearts a broadsword bears, the Queen of Hearts a rose." W. H. Auden.
0

#19 User is offline   whereagles 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 14,900
  • Joined: 2004-May-11
  • Gender:Male
  • Location:Portugal
  • Interests:Everything!

Posted 2014-June-10, 03:18

Ron, while I appreciate bidding discipline as much as you, laying unconditional confidence on it might be taking a good idea too far. As you know from practice, some people preempt twice and, what's more, get away with it. Even Robson/Segal admit that preempting twice may be right on occasion.

As for the hand in question, I admit I would have doubts on whether to pass or bid 6. I'll probably end up passing, but I certainly won't hang partner for bidding on :D
0

#20 User is offline   helene_t 

  • The Abbess
  • PipPipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 17,099
  • Joined: 2004-April-22
  • Gender:Female
  • Location:UK

Posted 2014-June-10, 03:55

View Postwhereagles, on 2014-June-10, 03:18, said:

Ron, while I appreciate bidding discipline as much as you

:)
The world would be such a happy place, if only everyone played Acol :) --- TramTicket
0

  • 2 Pages +
  • 1
  • 2
  • 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