BBO Discussion Forums: Bidding on or not? - BBO Discussion Forums

Jump to content

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

Bidding on or not? Vulnerable sacrifice?

Poll: Bidding on or not? (6 member(s) have cast votes)

What is your call?

  1. 6S (0 votes [0.00%])

    Percentage of vote: 0.00%

  2. Pass (6 votes [100.00%] - View)

    Percentage of vote: 100.00%

  3. Dbl (0 votes [0.00%])

    Percentage of vote: 0.00%

  4. Other (0 votes [0.00%])

    Percentage of vote: 0.00%

Vote Guests cannot vote

#1 User is offline   MP7601 

  • PipPip
  • Group: Members
  • Posts: 16
  • Joined: 2018-February-14

Posted 2021-October-04, 11:34



Playing with a solid partner against solid opponents. No special agreements, so Dbl should suggest defensive values, and pass would not be forcing.

(Edit) missed the form of scoring, which would be a team knockout match scored by IMPs.
0

#2 User is offline   akwoo 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,309
  • Joined: 2010-November-21

Posted 2021-October-04, 13:55

Form of scoring? If pairs (either MPs or IMPs), how good is the field?
0

#3 User is offline   mikeh 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 12,835
  • Joined: 2005-June-15
  • Gender:Male
  • Location:Canada
  • Interests:Bridge, golf, wine (red), cooking, reading eclectically but insatiably, travelling, making bad posts.

Posted 2021-October-04, 14:23

EW have guessed. Some pairs don’t play fit jumps, so some pairs won’t have this auction.

This means that some pairs may not bid slam.

If we assume that half the field plays 5C or 5D and half bid slam:

If slam makes and we go for 500-800, then we get 50% if slam makes and zero if slam fails.

If we go 1100, which seems very unlikely, we get zero all the time.

If we get out for 200, we’re still not getting a good score, since some pairs will get to ‘save’ in 5S, making and others will sometimes push the opps to a failing 6C.

So saving is low percentage. We’re basically betting that their slam makes and that we get out for less than 800, and that’s to get an average board.

I’d rather bet the other way…because if that’s right, then we’re getting a top or tied for top.

Save when they fail….odds on a zero. Save when they make…odds on average.

Defend when they make…zero or tied for zero. Defend when they fail…top or tied for top.

The smart money is on defending unless you’re convinced they make…and why should they? Maybe partner has J9xx or J10xx and a sure club trick? Maybe he has the heart Ace or they have two unavoidable heart losers….give partner 6=3=1=3, LHO 1=3=4=5 and RHO 0=3=5=5…hearts being Jxx Q10x Axx Kxxx around the table and so on.

Obviously saving could win, but it’s not my style.

I wouldn’t save at imps either.
'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

#4 User is offline   Winstonm 

  • PipPipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 17,190
  • Joined: 2005-January-08
  • Gender:Male
  • Location:Tulsa, Oklahoma
  • Interests:Art, music

Posted 2021-October-04, 14:31

I think I will take my chances that we have a club trick and a heart so I pass. I do see it as a close close call and it seems opponents have given away a lot of information that should help judge. I would guess east is like: void, Axxx,, AKxxx, Kxxx with west xx, Jx, Qxxx, AQxxx
"Injustice anywhere is a threat to justice everywhere." Black Lives Matter. / "I need ammunition, not a ride." Zelensky
0

#5 User is offline   DavidKok 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,234
  • Joined: 2020-March-30
  • Gender:Male
  • Location:Netherlands

Posted 2021-October-04, 14:38

I'm having a bit of trouble placing the hearts and the HCP around the table. How strong was the fit jump? The 2/3 or 3/5 comment places a lower bound, but I'd like to know in more detail.

I've assumed IMP scoring, at matchpoints it's an entirely different problem.

My initial guess: 3 shows an invitational raise probing 3NT and 5m, so a good 9 HCP minimum. Incidentally, very few players would bypass hearts to show a minor suit fitbid, so West is very unlikely to have four of them. East jumped to 6 over that and is looking at some monster hand with long diamonds and clubs, at least 5=5 but more likely 6=5 (and, again, not many hearts in either case) and basically all the honours in the minor suits that West doesn't have. It is not that uncommon for fit-jumps to show only four cards in the suit bid, but some pairs insist on at least 5. This would leave partner with approximately 5=5=0=3 or 5=4=0=4 and something like 7 points max (king of spades, ace of hearts) but more likely 5 or fewer (queen instead of ace of hearts).

With a presumed double fit and very few minor suit losers this might be a double slam swing. Picture East with, say, -, Ax, AKJTxx, KJTxx and partner with Kxxxx, QJxxx, -, xxx. But there is a lot of uncertainty - perhaps 6 might be off on a heart ruff, or perhaps 6 is down if partner has the ace of hearts and two rounds cash, or perhaps partner has a minor suit trick.
Now let's look for a horror scenario if we bid on. If neither opponent has psyched (if they did, my hat's off to them) partner is marked with diamond shortage and doesn't have long clubs either, so I don't think we are ever conceding more than one diamond trick (give East 5=5 minors and West 4=5 for the fitbid and we might lose the one diamond. Oh well). As both East and West have at most three hearts and East is strong, I think it is probable we don't concede more than two heart tricks. We might lose a spade as well, for 3 off in a slam at the worst. So bidding on is 'always' right if their slam makes, and might even have chances of making as noted above.
The last question: what is the chance that 6 makes? You said East is a solid opponent, which limits the motivation for 6 to two options. Either East expects to make, or East expects us to always bid 5M over 5, and is taking an advance sacrifice - something like x, Ax, KTxxx, KJxxx. But in this case, where are the points? We don't have them, partner doesn't have them, so that means West has a killer of a hand and 6 might again be a favourite to make.

I'm bidding 6, fully expecting to go down one or two against 6 making. On a bad day 6 is down and I might get a misguided lecture on expected value and cost-benefit analysis with pointed reminders of the vulnerability. On a good day 6 makes.
0

#6 User is offline   MP7601 

  • PipPip
  • Group: Members
  • Posts: 16
  • Joined: 2018-February-14

Posted 2021-October-05, 02:05

View Postakwoo, on 2021-October-04, 13:55, said:

Form of scoring? If pairs (either MPs or IMPs), how good is the field?


It’s from an online team match against opponents from another country, IMPs. I understand any concerns about playing pairs, but I was mainly worried about insurance against the opponents’ 6C.
0

#7 User is offline   MP7601 

  • PipPip
  • Group: Members
  • Posts: 16
  • Joined: 2018-February-14

Posted 2021-October-05, 02:06

View Postmikeh, on 2021-October-04, 14:23, said:

EW have guessed. Some pairs don’t play fit jumps, so some pairs won’t have this auction.

This means that some pairs may not bid slam.

If we assume that half the field plays 5C or 5D and half bid slam:

If slam makes and we go for 500-800, then we get 50% if slam makes and zero if slam fails.

If we go 1100, which seems very unlikely, we get zero all the time.

If we get out for 200, we’re still not getting a good score, since some pairs will get to ‘save’ in 5S, making and others will sometimes push the opps to a failing 6C.

So saving is low percentage. We’re basically betting that their slam makes and that we get out for less than 800, and that’s to get an average board.

I’d rather bet the other way…because if that’s right, then we’re getting a top or tied for top.

Save when they fail….odds on a zero. Save when they make…odds on average.

Defend when they make…zero or tied for zero. Defend when they fail…top or tied for top.

The smart money is on defending unless you’re convinced they make…and why should they? Maybe partner has J9xx or J10xx and a sure club trick? Maybe he has the heart Ace or they have two unavoidable heart losers….give partner 6=3=1=3, LHO 1=3=4=5 and RHO 0=3=5=5…hearts being Jxx Q10x Axx Kxxx around the table and so on.

Obviously saving could win, but it’s not my style.

I wouldn’t save at imps either.


Tend to agree with your comments in a pairs game, but would you buy insurance against 6C in a team match?
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