BBO Discussion Forums: +260 ATB - BBO Discussion Forums

Jump to content

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

+260 ATB

#21 User is offline   Jinksy 

  • Experimental biddicist
  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,909
  • Joined: 2010-January-02
  • Gender:Male

Posted 2014-December-12, 05:24

View Postrhm, on 2014-December-11, 13:29, said:

If you have a limit raise you can almost always construct hands for opener where the three level is too high.
If that is your worry I suggest go back to the old culbertson days where raising immediately to the three level was a slam invite.
Bridge is a game of percentages and calculated risks. Avoiding a negative score in all circumstances is losing Bridge.


Sure. I just don't see why E gets this logic applied and not W, whose hand had some extra playing strength too. Either could have invited and found the hand that was actually opposite or one that went straight down. E had exactly the hand he bid, and was a point under the nominal max. I don't think an extra trump improves a balanced hand so much that it's worth an upgrade.

So maybe it's the methods at fault, but a) unless you're playing several artificial bids between a 1M opening and 2m raise the 1M 2M sequence is always going to have an uncomfortably wide range, and b) it seems like the methods should drive the stronger hand to invite at the three level on a wider range than the weaker one, since the weaker one more often has an accept (and complementarily, the stronger one will invite less often).

This hand is tailor made for Bergen raises. But if you're not playing them (and I would not do so freely), or anything fancy to compensate, then IMO this is the type of hand on which you should get a bad result as a consequence.

I could change my mind as a result of sim data or some arguments that otherwise somehow isolated E on frequency grounds, but so far all the arguments in favour of E bidding more aggressively could as soon be targeted at W.
The "4 is a transfer to 4" award goes to Jinksy - PhilKing
1

#22 User is offline   rmnka447 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,366
  • Joined: 2012-March-18
  • Gender:Male
  • Location:Illinois
  • Interests:Bridge, Golf, Soccer

Posted 2014-December-12, 10:56

I'd give East the lion's share of the blame.

I'd make a limit raise with the East hand. How often do you hold a 9 prime HCP, 2 QT hand with 4 trumps and a ruffing value? The extra trump is big. You'd still make a constructive raise if a was a . And with that revised hand, you'd bid 3 over a 3 help suit game try. The extra trump adds more value, so that adds up to a limit raise IMHO.
0

#23 User is online   mikeh 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 12,855
  • Joined: 2005-June-15
  • Gender:Male
  • Location:Canada
  • Interests:Bridge, golf, wine (red), cooking, reading eclectically but insatiably, travelling, making bad posts.

Posted 2014-December-12, 13:21

Switch West's minors and game is virtually hopeless on a club lead, which seems probable....even if trump are 2-2, there is a good chance that the opps can play a 4th round of clubs.

So to some degree this is a matter of bad luck; the sort of thing that will inevitably happen when both partners take a similar view of their hands, whether it be a tad conservative or a tad aggressive (when the problem is atb for reaching a silly high-level contract)

My own view is that I don't like making limit raises with 4 bad trump and a flat hand with 9 hcp, and I don't like making constructive raises with 4 trump and a prime 9 count.

If my only choices on this hand were the underbid of 2 or the overbid of a limit raise, I go for the limit, simply because I have 3 controls, the 4th trump, and the diamond Q is in the same (long) side suit as the Ace, all of which makes the limit far less of an overbid than the constructive is an underbid.

I would personally prefer 3 constructive, over which opener can bid 3 as a generic game-try, which east would accept in a heartbeat. 3 is a slight push, and I don't think a signoff could be harshly criticized, but I think with the shape and the knowledge of the 9 card fit, the hand is worth the invite.

So my atb has to be to east, since given the methods, the underbid was a bit too little, and I just can't see West making a gametry opposite what will usually be 3 trumps. 3 card support is more common than 4 card.
'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

#24 User is offline   benlessard 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,465
  • Joined: 2006-January-07
  • Location:Montreal Canada
  • Interests:All games. i really mean all of them.

Posted 2014-December-13, 01:12

This hand just gave me an idea on how to easily test resulting bias in bridge.


You have an example hand like this where you make an ATB poll where you didnt bid game but made 6or7.

Give the same hand to others players and you tell them that game was missed but you made 4or5.

The difference of 2H/3H between the 2 group will give an idea of the resulting bias.
From Psych "I mean, Gus and I never see eye-to-eye on work stuff.
For instance, he doesn't like being used as a human shield when we're being shot at.
I happen to think it's a very noble way to meet one's maker, especially for a guy like him.
Bottom line is we never let that difference of opinion interfere with anything."
0

#25 User is offline   benlessard 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 3,465
  • Joined: 2006-January-07
  • Location:Montreal Canada
  • Interests:All games. i really mean all of them.

Posted 2014-December-13, 01:18

The other thing im thinking about is having 4 trumps raise without the QJ of trumps are quite different from those with good trumps.

Bad trumps are great to avoid trumps waste. Good trumps are great for dummy reversal if opener got a singleton.
From Psych "I mean, Gus and I never see eye-to-eye on work stuff.
For instance, he doesn't like being used as a human shield when we're being shot at.
I happen to think it's a very noble way to meet one's maker, especially for a guy like him.
Bottom line is we never let that difference of opinion interfere with anything."
0

#26 User is offline   aguahombre 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 12,029
  • Joined: 2009-February-21
  • Gender:Male
  • Location:St. George, UT

Posted 2014-December-13, 01:32

Again, there is no such thing as resulting bias in ATB. You are assessing blame for a result, not assessing how bad or wonderful particular actions were --- example...a clown trots out RKC with a worthless doubleton and a void, then bids 5N confirming all the keys. His partner, if paying attention, can then count 13 tricks and does not leap to the grand. No matter what our opinion of the clown, he is not the one to blame for the result.
"Bidding Spades to show spades can work well." (Kenberg)
0

#27 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-December-13, 02:46

View Postaguahombre, on 2014-December-13, 01:32, said:

Again, there is no such thing as resulting bias in ATB.


Although I mostly agree with you, there is some resulting bias in that people see the result and sometimes forget to realice that the best contract was just lucky, not good.
0

#28 User is offline   chasetb 

  • PipPipPipPipPip
  • Group: Full Members
  • Posts: 879
  • Joined: 2009-December-20
  • Gender:Male
  • Location:Podunk, backwater USA

Posted 2014-December-13, 03:23

View PostJinksy, on 2014-December-12, 05:24, said:

Sure. I just don't see why E gets this logic applied and not W, whose hand had some extra playing strength too. Either could have invited and found the hand that was actually opposite or one that went straight down. E had exactly the hand he bid, and was a point under the nominal max. I don't think an extra trump improves a balanced hand so much that it's worth an upgrade.

So maybe it's the methods at fault, but a) unless you're playing several artificial bids between a 1M opening and 2m raise the 1M 2M sequence is always going to have an uncomfortably wide range, and b) it seems like the methods should drive the stronger hand to invite at the three level on a wider range than the weaker one, since the weaker one more often has an accept (and complementarily, the stronger one will invite less often).

This hand is tailor made for Bergen raises. But if you're not playing them (and I would not do so freely), or anything fancy to compensate, then IMO this is the type of hand on which you should get a bad result as a consequence.

I could change my mind as a result of sim data or some arguments that otherwise somehow isolated E on frequency grounds, but so far all the arguments in favour of E bidding more aggressively could as soon be targeted at W.

While West does have good intermediates and decent shape, that Queen looks to be garbage (and is opposite East's hand), and the suit is WIDE open if you again don't know East's hand. I would give West a bad 16 points, so near the top of a minimum hand, but not enough to make any moves. What West didn't know about was that East had a LIMIT RAISE, something you don't need Bergen raises for. Yes Jinksy, there is a Santa Clause, and he would evaluate the East hand as a good 11 dummy points -> 9 HCP + 1 for Kx (don't tell me you downgrade that!) + 1 (and change) for a combination of all your points located in two suits and having more controls than the expected average.

Something else I do is when I have extra trump beyond what a bid promises, I add points. Since 2 promises only 3, I add an extra point, and even precluding my second upgrade above that puts you at 11, too high for a constructive raise. I also went ahead and put that hand into the K&R hand evaluator just to see if they would upgrade it - they call it 15.10 while Danny Kleinman calls it between 13.67 - 13.99 . So even I, who apparently over-evaulated the West hand, looks vindicated in not doing anything over 1 - 2.
"It's not enough to win the tricks that belong to you. Try also for some that belong to the opponents."

"Learn from the mistakes of others. You won't live long enough to make them all yourself."

"One advantage of bad bidding is that you get practice at playing atrocious contracts."

-Alfred Sheinwold
1

#29 User is offline   aguahombre 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 12,029
  • Joined: 2009-February-21
  • Gender:Male
  • Location:St. George, UT

Posted 2014-December-13, 09:45

View PostFluffy, on 2014-December-13, 02:46, said:

Although I mostly agree with you, there is some resulting bias in that people see the result and sometimes forget to realice that the best contract was just lucky, not good.

Very true. My rant/campaign ad nauseum is that ATB begins with a result. Determining the cause is not being a "result merchant". We don't need to sell what is already provided free of charge.

Certainly, opinions about whether the players' actions were good or bad is valuable input. But, we should be able to attribute credit for a lucky result or blame for an adverse result regardless. The person who made the worst decision is not necessarily the person responsible for the end product.

IMO, the bias in these polls comes from being blinded by bids or plays (or systems) which we really hate --- not from knowing the result.
"Bidding Spades to show spades can work well." (Kenberg)
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