BBO Discussion Forums: Forcing Pass (threadjack) - BBO Discussion Forums

Jump to content

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

Forcing Pass (threadjack)

#1 User is offline   jillybean 

  • hooked
  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 10,137
  • Joined: 2003-November-15
  • Gender:Female
  • Location:Vancouver, Canada
  • Interests:Multi

Posted 2011-May-05, 14:02

This is an auction Adam posted in another thread. http://www.bridgebas...4-forcing-pass/

1 - 2 - 3(1) - Pass
3 - X(2) - Pass - 3
Pass - Pass - 4 - 4
Pass - Pass - ???

(1) Limit raise or better of diamonds
(2) Takeout

I am in the process of developing FP rules, including "Besides hands where the partnership is in a game forcing auction, forcing pass also applies when one hand opens and the other hand shows at least invitational values" and this auction & comments raised a lot of good points.

I was under the belief that the balance of the points was enough to create a FP situation, others say you need game values.
I see it could depend on vulnerability and the auction, if there was extreme distribution but that doesnt appear to be the case here.

In the posted auction, unless partner has pscyhed or opened on a sub minimum, we have the balance of the points. Should we let the opps play in an undoubled game or even part score?
"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

#2 User is offline   nigel_k 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,207
  • Joined: 2009-April-26
  • Gender:Male
  • Location:Wellington, NZ

Posted 2011-May-05, 14:26

A limit raise should not establish a force, even if you decide that other invitational sequences do.

In the actual sequence, your side was almost certainly going to play 4 as West has limited their hand (twice) and East's sequence is not invitational. Why should you be compelled to double when your side only has a part score?
0

#3 User is offline   gnasher 

  • Andy Bowles
  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 11,993
  • Joined: 2007-May-03
  • Gender:Male
  • Location:London, UK

Posted 2011-May-05, 14:44

When we have game values, it's usually a good thing to be playing a forcing pass, because it has a large upside - we can expect either a game bonus or a decent penalty, and the forcing pass helps us to work out which we should play for. Sometimes, of course, it goes wrong, and we end up doubling something that makes, or bidding on when nothing makes. However, that's rare.

When we know that we have invitational values and we might have game values, there's still a reasonable case for playing a forcing pass. A game bonus or a penalty is still possible, and playing a forcing pass increases our chance of getting it. Against that, the risk that they can make their contract has gone up too. Arguably the upside of a forcing pass is still greater than the downside.

When we know that we don't have game values, the upside is much less, because we don't expect to make a game. Also, the risk of doubling them when they're making is greater, because our average strength is lower.

That's mainly an IMPs argument. At matchpoints, you might take the view that when we have an invitation opposite an opening, if they make their partscore we're going to get a bad score, so we should play a forcing pass. The upside is maximising our plus score, which will usually be a big gain; the downside is only turning a poor score into a worse one. I've never considered this before, but maybe your forcing-pass agreements should vary according to the form of scoring.
... that would still not be conclusive proof, before someone wants to explain that to me as well as if I was a 5 year-old. - gwnn
1

#4 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 2011-May-05, 15:11

To threadjack your threadjack, you don't have any need to play a forcing pass on the quoted auction. Opener tried to sign off in 3D. If responder wanted to set up a forcing pass auction she could have redoubled (which would set up a FP) so responder is also limited. Opener then passed over 3H showing no desire to compete further. Responder could have made a game try of some form (3S, 4C) but instead just bid a competitive 4D. Now the opponents bid again. I can't see why the opening side would ever bid 5D on this auction, so if one of them thinks 4H is going off, they double. If they don't, they pass.
0

#5 User is offline   bluecalm 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,555
  • Joined: 2007-January-22

Posted 2011-May-05, 15:12

My forcing pass rules:
a)When we forced to game below game
b)When they clearly wanted to play only partscore and then are bidding over our game contract
c)If we make strong redouble (forcing up to 2NT) or we make strong double over their 1NT (forcing after 2m by them)
d)If they jump preempt to 5level being white vs us being red

That's about it. Simple obvious rules and no guessing game.
I also like to play that every double is t/o if we didn't have agreed suit regardless if it's forcing or not forcing situation to avoid further confusion but this is probably too modern for most :)

Also possible is to add:
e)if we forced ourselves to 2M pass is forcing below 2M (drury etc.) but this doesn't hold on 3level of course (because in competitive auctions overcall could be really weak and we don't want to bid 3M despite partner making limit raise forcing us to).

Some people I know like the rule:
f)if we bid game being red vs white

but I think it's a weak rule. I would happily play it if we change "game" to 3NT though and maybe even extend it to every 3NT bid which must be constructive (like 1m - 3NT) but I would have to think about it. (I am really not comfortable playing 1D - 2C - 3NT - 4C - pass as forcing if they are vul and we are not at imps).
0

#6 User is offline   peachy 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,056
  • Joined: 2007-November-19
  • Location:Pacific Time

Posted 2011-May-05, 20:22

I keep bringing up this link, but I think it is a good one, discussion of FP. The "rules" of FP can be simple, or they can be complicated. Make them simple for your own comfort. Even world class experts do not agree amongst themselves what the *right* rules are.
http://www.districts...%202009-06.aspx
0

#7 User is offline   Yu18772 

  • PipPipPipPip
  • Group: Full Members
  • Posts: 466
  • Joined: 2010-August-31
  • Gender:Female
  • Location:Los Angeles

Posted 2011-May-05, 23:54

View Postjillybean, on 2011-May-05, 14:02, said:

This is an auction Adam posted in another thread. http://www.bridgebas...4-forcing-pass/

1 - 2 - 3(1) - Pass
3 - X(2) - Pass - 3
Pass - Pass - 4 - 4
Pass - Pass - ???

(1) Limit raise or better of diamonds
(2) Takeout

I am in the process of developing FP rules, including "Besides hands where the partnership is in a game forcing auction, forcing pass also applies when one hand opens and the other hand shows at least invitational values" and this auction & comments raised a lot of good points.

I was under the belief that the balance of the points was enough to create a FP situation, others say you need game values.
I see it could depend on vulnerability and the auction, if there was extreme distribution but that doesnt appear to be the case here.

In the posted auction, unless partner has pscyhed or opened on a sub minimum, we have the balance of the points. Should we let the opps play in an undoubled game or even part score?



The balance of points doesn't mean they are going down, it gives you a better chance, the more points you have the better your chances get. Thats not a good enough reason by itself. It has to be that in the long run your X brings more points than it looses. However, the closer your point range to 20-20 the larger the role of the distribution an the lesser of your points. Also, distributional partner could open subminimal hand and I see no reason to hang him for that. Although considerations of wether the double is "worth it" in IMP and MP is different, but in general I think that in competition if we pushed them one level above what they were content to play we will get a good result if they go down anyway, but we may make the bad result much worse (if they make).

Here is a very crude example of 2 calculations for IMP and MP:
IMP
Lets say we bid 4 and they sac at 5 going on average 2 down, all NV, but we don't have 5. Now I need to minimize the loss - If I don't double I lost 320, if I do I lost 120, I stand to gain ~200 from the X. If they make I loose additional 150 because of the double. Thus as long as the odds at least are ~40% or more that they go down I am fine doubling in the long run. Given the point balance (~25-15 or better) I would expect them to be down more than 40% of the time in a sac, sometimes only -1 but also sometimes -5.
Now if we do the same calculation for invitational hands where the point distribution is closer to 20-20, and thus they are more likely to make or not to go as much down. For example - in the given auction (assuming 4 even makes) -we had 130, they went to 4 that is potentially -1. My gain if they go down is a 50/100, my loss if they make is 150, I need 66% chances if they vul or 75% if they non vul to make it worth doubling - thus I double in these auctions only if I think we are in that type of % range, which means only if I have a good reason.
If they are in 4 of a minor it is even worse because you stand to loose 380-580 (pending vulnerability) form the X if they make, and gain only 50-100 if they dont.
So forcing to bid or double in these situations makes less sense in the long run.

MP
In MP the situation is a even more complex, and it depends very much on what you think is going on at the other tables.
Shortly - in the game-sac situation double may be your only way to get anything but bottom, so your potential loss from the double is minimal and potential gain is maximal (assuming your game makes, and that at most other tables your side will be playing there).
In the 20-20 situation, in Adam's example:
- if the field is in 3 making 4 - x converts bottom to top if 4 is -2 (NV) or -1 (Vul), if they are -1(NV) or better you get a bottom anyway, then it might be right to try 5, but in any case this looks like they got you.
- if the field is likely to be in 4 which goes down, or let your ops play 3 that makes - then a plus score (4 down) will be top, and a minus (4 making) will be a bottom - doubled or not. In this case you dont gain from the double, but it may potentially let them find otherwise unlikely winning play.....and convert your top to bottom.
So again - this seems to be too variable situation to force bidding.
Yehudit Hasin

"But I don't want to go among mad people," Alice remarked.
"Oh, you can't help that," said the Cat: "we're all mad here. I'm mad. You're mad."
"How do you know I'm mad?" said Alice.
"You must be," said the Cat, "or you wouldn't have come here."
0

#8 User is offline   gnasher 

  • Andy Bowles
  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 11,993
  • Joined: 2007-May-03
  • Gender:Male
  • Location:London, UK

Posted 2011-May-06, 02:16

Consider this auction, at matchpoints with both sides vulnerable:

1 2 3 dbl
pass pass 3 pass
pass 4

3 showed a high-card raise. Advancer's double showed diamond support. Opener's pass invited game.

From the auction, we can expect that:
- We have the balance of the strength.
- 4 is against the odds, but it may still be making.
- The matchpoint difference between +100 and +200 will be large.
- The matchpoint difference between -130 and -710 will be smaller.

So, even though we've settled in a partscore, shouldn't pass be forcing?
... that would still not be conclusive proof, before someone wants to explain that to me as well as if I was a 5 year-old. - gwnn
0

#9 User is offline   bluecalm 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,555
  • Joined: 2007-January-22

Posted 2011-May-06, 02:35

Quote

- The matchpoint difference between +100 and +200 will be large.
- The matchpoint difference between -130 and -710 will be smaller.

So, even though we've settled in a partscore, shouldn't pass be forcing?


It's not sure thing if matchpoint difference between -130 and -710 will be small despite being smaller than between +100 and +200.
You also didn't mention matchpoint difference between -200 and -130 which will be huge and difference between -100 and -130 which may not be that big.
Having an option to let them play 4 not doubled when we are clearly not making 4 and they will often make is valuable option imo. It's not like forcing pass is magically solving all the problems. It increases our bidding precision just a bit but it costs an option of passing it out, this option needs to be worth close to nothing to make forcing pass worthwhile.

In such sequencies like yours it's not even sure thing what should pass mean. Usually FP should show something specific, like shortness in their suit to make partner's decisions simple. Here FP would mean:
"Partner I think we could belong to 4 despite me not forcing to game and rejecting your invite before, but please don't pass!"
While normal not forcing pass would mean:
"I don't see any reasons to double them nor to think 4 makes, what do you think ?".

I don't see what you could gain by pass being forcing here really.
0

#10 User is online   awm 

  • PipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 8,375
  • Joined: 2005-February-09
  • Gender:Male
  • Location:Zurich, Switzerland

Posted 2011-May-06, 08:25

It may be worth considering the purpose of forcing passes.

The idea is that there may be a situation where the opponents bid something, and I am sure they are going down, yet I do not want to just double. This is normally because I think there is a good chance we will make a contract that will be worth more than what we get from defending (either a game or slam our way). If pass is not forcing, my passing on this hand would risk defending undoubled when I know their contract is failing. But doubling would often lead to defending doubled when we get a better result some other way.

If the auction is such that our chances of making a higher contract are very slim, there is no reason to play pass as forcing. If I'm pretty sure they're going down I can double; if I'm not sure, I can pass. If partner passes it out that's okay.

The auctions like those presented in this thread seem indicative that it's very unlikely we can make a higher contract. We have already tried to play in a partial and the opponents have bid over it. If I'm sure we are setting them, I should double... since the chances of our making the game contract we have already rejected cannot be that good.

How about the following simple rule? Pass is forcing when both: (1) We have guaranteed at least game-invitational values combined (2) The person passing has never limited his hand to a narrow range.

The auctions so far in this thread fail the second count, in that the person passing has already tried to sign off in a partscore. This rule also emphasizes that forcing pass is about situations where our combined assets are not very well established, such that it might be appealing to pass even though we have them beat (i.e. as a slam try).
Adam W. Meyerson
a.k.a. Appeal Without Merit
0

#11 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 2011-May-06, 09:26

Having clear agreements is the number one goal when dealing with forcing pass. Inv or more hands is suboptimal, but if its not a long temr partnership its a good approach IMO.

A good improvement would be that invitational bids do not create forcing pass (non forcing bids at the 3 level mostly), but inv+ (cuebids or redoubles) do create forcing pass, unless made by a passed hand because then they are just invitational.
0

#12 User is offline   Phil 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 10,092
  • Joined: 2008-December-11
  • Gender:Male
  • Location:North Texas, USA
  • Interests:Mountain Biking

Posted 2011-May-06, 10:06

View Postbluecalm, on 2011-May-05, 15:12, said:

My forcing pass rules:
...

d)If they jump preempt to 5level being white vs us being red



I assume this is if we take a call over the initial preempt?
Hi y'all!

Winner - BBO Challenge bracket #6 - February, 2017.
0

#13 User is offline   bluecalm 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,555
  • Joined: 2007-January-22

Posted 2011-May-06, 14:55

Quote

I assume this is if we take a call over the initial preempt?


No. I am not big fan of this rule but people here insist on playing it and I don't mind much red vs white.
3 - 3 - 5 - pass is forcing according to this rule.
My personal preference is to scratch it :)
0

#14 User is offline   Phil 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 10,092
  • Joined: 2008-December-11
  • Gender:Male
  • Location:North Texas, USA
  • Interests:Mountain Biking

Posted 2011-May-06, 15:15

View Postbluecalm, on 2011-May-06, 14:55, said:

No. I am not big fan of this rule but people here insist on playing it and I don't mind much red vs white.
3 - 3 - 5 - pass is forcing according to this rule.
My personal preference is to scratch it :)


There is logic in (3x) - "anything but a pass" - (5x) - "forcing pass"

It would be strange to play (3x) - "pass" - (5x) - "forcing pass" - but thats what your rule means.
Hi y'all!

Winner - BBO Challenge bracket #6 - February, 2017.
0

#15 User is online   Cyberyeti 

  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 14,215
  • Joined: 2009-July-13
  • Location:England

Posted 2011-May-06, 16:01

Another very normal but not universal FP rule is where we've committed ourselves to bidding X, passes are forcing below X.

Eg playing 1-2N as a good raise to at least 3 but not FG 1-P-2N-3-P is forcing

Ditto 1-P-2(inverted) commits us to 3 the way we play, so pass over a 2M overcall is forcing.

Another one we play is that if we double 1N for penalties, we won't sit 2m undoubled so pass is forcing.
0

#16 User is offline   bluecalm 

  • PipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,555
  • Joined: 2007-January-22

Posted 2011-May-06, 18:33

Quote

There is logic in (3x) - "anything but a pass" - (5x) - "forcing pass"

It would be strange to play (3x) - "pass" - (5x) - "forcing pass" - but thats what your rule means.


Yeah, I didn't put it correctly. Thanks for the correction.
0

#17 User is offline   dake50 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 2,211
  • Joined: 2006-April-22

Posted 2011-May-06, 23:17

I play 3C: limit+ has DT that 3D doesn't, 3D has some shape.
So I can suggest 3+tricks by prime cards vs. 3 tricks by short side.
Essentially *my choice* is to establish FP with 3C.
0

#18 User is offline   jdeegan 

  • PipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 1,427
  • Joined: 2005-August-12
  • Gender:Male
  • Interests:Economics
    Finance
    Bridge bidding theory
    Cooking
    Downhill skiing

Posted 2011-May-07, 02:11

:D I admire your fortitude in trying to refine the time honored rule: if our side voluntarily bid or has forced the bidding to a game to make, then the pass is forcing - otherwise not. Remember that MP's and IMP's are different animals. With MP's you have to guess exactly right else disaster, whereas at IMP's the difference between -500 and -420 is minor.

On the hand in question, partner showed a weak hand with some length. I think a pass over 4 is not only possible, but advisable.
0

#19 User is offline   han 

  • Under bidder
  • PipPipPipPipPipPipPipPipPipPip
  • Group: Advanced Members
  • Posts: 11,797
  • Joined: 2004-July-25
  • Gender:Male
  • Location:Amsterdam, the Netherlands

Posted 2011-May-07, 07:35

View Postgnasher, on 2011-May-06, 02:16, said:

Consider this auction, at matchpoints with both sides vulnerable:

1 2 3 dbl
pass pass 3 pass
pass 4

3 showed a high-card raise. Advancer's double showed diamond support. Opener's pass invited game.

From the auction, we can expect that:
- We have the balance of the strength.
- 4 is against the odds, but it may still be making.
- The matchpoint difference between +100 and +200 will be large.
- The matchpoint difference between -130 and -710 will be smaller.

So, even though we've settled in a partscore, shouldn't pass be forcing?


First of all, I prefer to play with the same agreements at matchpoints and at IMPs. At IMPs, the difference between -130 and -710 is probably much larger than the difference between +100 and +200. Rather than changing the agreement, if I believed in your claims above, I would just double more often at matchpoints.

But I'm not even convinced that your claims are correct. If you could convince me that the diffference between -130 and -710 is zero then I would agree that pass *should* be forcing at matchpoints, but I don't see wy this is the case. I also don't see why we should expect that we have the balance of strength, both opener's pass and responder's 3D can be based on distribution. So no, I don't think this pass should be forcing, and I certainly don't want it to be forcing.
Please note: I am interested in boring, bog standard, 2/1.

- hrothgar
0

#20 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 2011-May-07, 09:23

View PostPhil, on 2011-May-06, 15:15, said:


It would be strange to play (3x) - "pass" - (5x) - "forcing pass" - but thats what your rule means.


I've known a (pretty good) pair who played this.
We also made +550 in the spring 4s on the auction 3D P 5D x when the doubler had nothing resembling a double, and I wonder if he was playing the same.
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