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You should open the bidding if...

#1 User is offline   EricK 

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Posted 2006-November-23, 13:29

Various "authorities" will give different opinions as to what constitutes an opening bid - 12 HCP, rule of 20, 26 Zars etc etc.

But what is the reasoning which underlies any of these rules of thumb?

I suspect it is something like one of these:

a) you should open the bidding if the chance that you can make game is above some probability, g

:rolleyes: you should open the bidding if the chance that the highest making contract is your way is above some probability, c

c) you should open the bidding if the chance that the par score is your way is above some probability, p

The reason I think this is that it tries to relate whether to open or not to some concrete bridge related statistic rather than to some arbitrary scale.

Do you think I am on the right track here? And if so, what is the approximate value of these probabilities?
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#2 User is offline   Stephen Tu 

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Posted 2006-November-23, 13:42

You can't just make blanket statements that "this hand should be opened", and "this hand should not be opened". It's system dependent. Some systems are designed to be able to show very light opening bids without partner hanging you. Others aren't.

The fundamental rule, IMO, is "open this hand if you think, given your system agreements, in the long run your net score will be higher by opening than it will be by passing." Net score includes potential losses/gains on other boards due to increased/decreased opening bid ranges affecting your accuracy.
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#3 User is offline   Echognome 

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Posted 2006-November-23, 13:54

Agree very much that it is system dependent. I also believe it's position dependent. It's quite clear that people treat 3rd in hand openers much different from 1st, 2nd, or 4th openers. 4th seat openers tend to be sounder than all other positions.

I think you are addressing some of the issues concerned with opening, but don't forget things like directing the lead, helping the defense (but don't forget you are simultaneously helping declarer), and disrupting your opponents bidding machinery. Also in regards to par, there are many versions of par (see S.J. Simon for a good discussion of this) and of course opening affects all of these.

I'm not saying it's not an itneresting debate, just that there are a lot of factors to consider.
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#4 User is offline   EricK 

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Posted 2006-November-23, 14:01

Stephen Tu, on Nov 23 2006, 07:42 PM, said:

You can't just make blanket statements that "this hand should be opened", and "this hand should not be opened". It's system dependent. Some systems are designed to be able to show very light opening bids without partner hanging you. Others aren't.

The fundamental rule, IMO, is "open this hand if you think, given your system agreements, in the long run your net score will be higher by opening than it will be by passing." Net score includes potential losses/gains on other boards due to increased/decreased opening bid ranges affecting your accuracy.

Yes it is system dependant, but given any system I still think there must be an underlying reason why some hands should be opened and some not. An underlying reason relating to how likely you are to reach various sorts of contract. A reason why opening a hand leads to a higher average score than passing it.
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#5 User is offline   neilkaz 

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Posted 2006-November-23, 14:44

I'll stir the pot a bit and state that you should open the bidding with a forcing bid if there's a very good chance to make game opposite a hand PD will pass if you just open with a 1 bid.

Yes..what I am saying is that they typical "American" 2 system can and should be improved.

Food for thought ?!?.., anyhow I am off to enjoy my turkey .. neilkaz ..
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#6 User is offline   Robert 

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Posted 2006-November-23, 17:02

Hi everyone

Bidding is a matter of the partnership 'likes.'

The current trend appears to be to open with weaker and weaker hands. Some exceptions continue to exist. One Italian pair currently plays a virtually unlimited one bid opening. Roth Stone cut a path in American bridge starting in the 50s(?) with their 'very sound' openings and solid 'free bid' standards.

I suspect that most people like to bid, so they use a method that allows them to open more hands. Precision methods seem to have spread because they allowed more bids with hands that were passes using other methods.

My Precision style from several decades ago was to play Precision '2 up and 2 down.' We played Precision with 1st and 2nd seats using ranges 2HCP lower and 3rd and 4th seats using ranges that were two HCP higher. 9-13HCP was the limited opening range in 1st and 2nd seats.

Since we opened so light, we used a slightly more conservative style in 3rd and 4th seat. It was fun and we were able to bid more hands. Responder merely 'added' or subtracted' 2HCP to make the proper bid.

IMO a system is chosen because a pair 'likes' to bid using 'that style.' Almost any good system will produce good results 'given a decent' partnership. A lesser pair will simply not produce the same results 'even' if they are trying to play the exact same methods.

The Blue Team destroyed virtually all competition for several decades using an assortment of systems(Roman and Blue Team were just two of their bidding methods)

I have seen comments that the Italians of those same years would have still won playing the methods of the other teams. I have little doubt that this was true.

I currently play a highly modified Big Club system(it started out as Precision) so I think that the problem with typical "American" 2C methods has already been solved. :rolleyes:

The advantages of a big club system are mainly gained from using the 'limited' bids.

Regards,
Robert
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#7 User is offline   zasanya 

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Posted 2006-November-23, 20:27

My Guru explained it this way about 25 years (may be more :-)) ago.
There are 40 points in the pack using the Milton Point count.The number of tricks is 13.So average is 10 points per hand and 3 points per trick.The opener should be 1 trick more than average .Hence 10+3 is a sound opening.Over the years people refined the Milton Point, enhanced the value of Aces and kings and long suits and started opening on lighter hands.
The main advantage of precision in my opinion is the various gadgets available after the 1 opening which leads to better slam contractsIt is the 16+ hands which are difficult to describe in natural methods.Precision makes it easy if there is no interference.Alas these days thats a big if.
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#8 User is offline   sceptic 

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Posted 2006-November-23, 20:35

to open you need 0-40 hcp and at least 0 cards in the suit you bid

You just need to find something that suits you

I DOUBT there is a right or wrong answer unless you start making it system specific, anyway that is my pearl of wisdom today
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#9 User is online   jillybean 

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Posted 2006-November-23, 21:03

Maybe its just me but when I ask this question or respond to the same I am using sayc, 2/1 standard type bidding not Clauses version of Regres, Moscito or any other fringe system, lets not make it more difficult than it already is :)
"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
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#10 User is offline   inquiry 

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Posted 2006-November-23, 21:06

You should open the bidding if...
  • You have an opening hand
  • you really want partner to lead a particular suit
  • you think by opening you might make it more difficult for the opponents to get a good result (psyche)
  • it is your turn to bid and you want too

--Ben--

#11 User is offline   rbforster 

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Posted 2006-November-23, 21:11

Don't forget this one - any other action would imply a stronger hand than you have and would hence mislead partner. 2 fert here we come...
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#12 User is offline   matmat 

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Posted 2006-November-23, 21:13

inquiry, on Nov 23 2006, 10:06 PM, said:

You should open the bidding if...
  • it is your turn to bid and you want too

I'm with Ben.
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#13 User is offline   pbleighton 

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Posted 2006-November-23, 21:32

"Maybe its just me but when I ask this question or respond to the same I am using sayc, 2/1 standard type bidding not Clauses version of Regres, Moscito or any other fringe system, lets not make it more difficult than it already is"

Even within your parameters, system and agreements matters. I am definitely more aggressive playing with some people than others, and am more aggressive playing SA than 2/1.

With SA or 2/1, if you agree to pass the majority of (literal, unadjusted) 12 counts, this is definitely a playable style (though I wouldn't want to play it for aesthetic/fun reasons). With SA, you can also agree to open most 11 counts/good 10 counts, and this is also playable. The definitions of weak, invitational, and GF hands by the responder obviously will differ between these two styles.

I prefer a light style (actually weak/mini NT too), but with a pickup pd playing "SAYC" (whatever that turns out to be), I tend to be pretty literal, opening 11 counts only when 5-5 or with a 6 card suit, and the hand looking pretty good otherwise (not too quacky, no unguarded honors, reasonable suit(s) quality). I probably "should", in this case, pass bad 12 counts, but somehow I never feel like it :)

Peter
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#14 User is offline   the hog 

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Posted 2006-November-23, 23:31

When should you open the bidding?

Well this is dependent on many things, the primary one being system. And system is to a very large extent dependent on your philosophy, approach, likes and dislikes and attitude to the game.

There are differing philosophies in play here, a fact which has already been alluded to by some of the posters above. There is a big difference in attitude between 2 handed and 4 handed bridge. US players seem to greatly prefer 2 handed bridge; that is they like to have a meaningful dialogue with their partners and attempt to bid to the best contract possible. This is reflected in the regulations in force in the States and also in many European countries, where a conservative approach to the game is taken.

Players from some other countries prefer to play 4 handed bridge. That is the realization that there are 4 players at the table and that we should try to make life as difficult as possible for the other side AS WELL AS trying to find a good place to play for us.
This style is characterised by light openings, frequent and undisciplined pre empts, frequent obstruction and the use of systems such as Moscito, strong pass systems with their ferts and 8-12HCP opening bids etc etc.

This is not an argument that one philosophy is superior to the other, simply the acceptance that 2 or more views exist. The regulations of governing bodies reflect this. Regulators dislike the 4 handed game because it is more adverserial and thus can lead to friction at the table from "social player" or those who are simply unwilling to understand. A typical "knee jerk" reaction can be seen by the response taken to Bergen 2 under pre empts in the States, and in the almost hysterical reaction by administrators in the WBF such as Damiani to anything that is different from the norm.
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#15 User is offline   EricK 

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Posted 2006-November-24, 01:31

OK thanks for all the responses. But I am not asking what style of opening is better than others or anything like that.

Let me give an example:

Compare AQxxx AJxx xxx x with x xxx AJxx AQxxx. These hands have exactly the same trick taking power on average, so in that sense they are as strong as each other. But because of the way bridge bidding and scoring work the former is a much more useful hand than the latter - in a bridge sense it is a stronger hand.

Now this difference in strength actually relates to things like the probability that your side can make the highest contract (because majors can outbid minors) or the probability that the par contract is your way (for the same reason), or the probability that your side can make game (because ten tricks in a major happens more often than eleven tricks in a minor). So the actual strength of a hand should be fundamentally linked to these sorts of statistics.

eg Take a system such as Moscito. This divides opening hands into four types - "strong" hands (which open 1), slightly weaker hands (which open with 1 - 2), still weaker hands with distribution (which open with a pre-empt) and finally all the other hands (which pass). For simplicity's sake the borders between these groups are expressed in terms of various HCP and distribution Points. But a hand is strong because it has a certain number of points, it is strong because it is more likely to make various sorts of contracts.

So theoretically the dividing line between these groups could (should?) be expressed in terms of the sorts of things I listed. And I suppose I was really just wondering what those dividing lines are (for various systems).
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#16 User is offline   hrothgar 

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Posted 2006-November-24, 06:54

You've opened a very complicated can of worms and I doubt that you are going to find a very satisfactory answer. From my perspective, the only system designers that were really studying these types of issues seriously were the various light opening theorists; most of whom gave up on this type of work when it became apparant that the the regulatory authorities were more interested in preserving the status quo than in technical merit of different approaches to bidding. Accordingly, what you are going to see is silly little rules of thumb like the you want 13 HCP because this is one trick stronger than average.

Here are the break points for MOSCITO taken from my system notes. I given up on using HCPs or adjusted HCPs or Zar points or anything like that. I prefer providing example hands.

Constructive openings promise 6+ Slam points. Extreme two suiters with 10+ cards in the two longest suits require 5 slam points

Minimum unbalanced hands suitable for a constructive opening

32
KJ74
6
AJT932

64
A2
QT976
K975

KT872
A5
Q2
T653

9
AT9753
A65
842

J87643
AK94
6
J3

Balanced hands require more High Card strength than unbalanced

KQ65
QT3
QT32
Q9

K3
87632
A73
A32

J42
KT6
KJ86
K42

QJ852
A9
K73
J75

A932
KJ
QJ7
T762

Here's a bunch of hands that I think are right on the dividing line between a strong club and a constructive opening

Q3
AKJ73
K
Q8754

J
AQ54
AQ96
Q843

AKJ4
J
KJ863
Q87

K643
AQJ62
Q
K62

Q98543
Q
AK
KJ74

QT2
KQ4
KQ3
QJ62

The boundary conditions between pass and preemptive openings are a lot more complicated. Issues like suit quality are often a lot more important than the raw strength of the hand.
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#17 User is offline   csdenmark 

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Posted 2006-November-24, 08:23

hrothgar, on Nov 24 2006, 02:54 PM, said:


Constructive openings promise 6+ Slam points.  Extreme two suiters with 10+ cards in the two longest suits require 5 slam points

Minimum unbalanced hands suitable for a constructive opening

32  
KJ74 
6   
AJT932

64
A2
QT976
K975

The boundary conditions between pass and preemptive openings are a lot more complicated.  Issues like suit quality are often a lot more important than the raw strength of the hand.

Referring to the old quick trick counting?

----------------------------------------

hrothgar, on Nov 24 2006, 02:54 PM, said:

You've opened a very complicated can of worms and I doubt that you are going to find a very satisfactory answer.  From my perspective, the only system designers that were really studying these types of issues seriously were the various light opening theorists; most of whom gave up on this type of work when it became apparant that the the regulatory authorities were more interested in preserving the status quo than in technical merit of different approaches to bidding.  Accordingly, what you are going to see is silly little rules of thumb like the you want 13 HCP because this is one trick stronger than average.


In my book by Slawinski/Ruminski "Introduction to weak opening systems" they are operating with a term called 'aggressiveness'. Anybody who knows what that term means?

They also have a figures for several of the systems:

Regres - Mean opening 2.19
BezNazwy - Mean opening 2.18
Lambda - Mean opening 2.09
Antidelta - Mean opening 2.32
Sigma - Mean opening 2.47
Big Beat - Mean opening 1.92
Delta - Mean opening 1.8
Beta - Mean opening 2.09

As I understand it means something like the higher the figure the more aggressive the system is.

Anybody who really knows about this?

Anybody who knows how to construct such calculations?
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#18 User is offline   hrothgar 

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Posted 2006-November-24, 08:35

>>The boundary conditions between pass and preemptive openings are a lot more
>>complicated. Issues like suit quality are often a lot more important than the raw >>strength of the hand.

>Referring to the old quick trick counting?

When I play MOSCITO, my 2 shows 4+ Diamonds and 4+ cards in either major. In my experience, this opening works better if opener promises Hxxx in the major (alternative, any 5 card suit is fine). Accordingly, I'd open 2 holding

Q963
6
87542
KJ3

I'd pass holding

8754
6
Q9632
KJ3

>In my book by Slawinski/Ruminski "Introduction to weak opening systems" they
>are operating with a term called 'aggressiveness'. Anybody who knows what that
>term means?

The mean opening for a bidding system descibes the expected bidding level for the opening structure. Each opening bid in the system is represented by two numbers.

1. The number of steps of bidding space used (Pass = , 1 = 1, 1 = 2, ...)
2. The frequency of the opening bid. (pass occurs on 32% of all hands, 1 on 15% of all hands, 1 on 11% of all hands, ...)

Multiply the frequency of any opening by the number of steps of bidding space and sum across all openings. If one assumes that all preemptive openings are equally difficult to defend against the metric provides a decent description of the preemptive effect of the bidding system.
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#19 User is offline   csdenmark 

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Posted 2006-November-24, 09:58

hrothgar, on Nov 24 2006, 04:35 PM, said:

>In my book by Slawinski/Ruminski "Introduction to weak opening systems" they
>are operating with a term called 'aggressiveness'. Anybody who knows what that
>term means?

The mean opening for a bidding system descibes the expected bidding level for the opening structure.  Each opening bid in the system is represented by two numbers.

1.  The number of steps of bidding space used (Pass = , 1 = 1, 1 = 2, ...)
2.  The frequency of the opening bid.  (pass occurs on 32% of all hands, 1 on 15% of all hands, 1 on 11% of all hands, ...)

Multiply the frequency of any opening by the number of steps of bidding space and sum across all openings.  If one assumes that all preemptive openings are equally difficult to defend against the metric provides a decent description of the preemptive effect of the bidding system.

Sorry Richard I dont understand much of that. The systems I mentioned are all pass-systems. I doubt the 0-7HcP(1=2) opening is so very interesting and I wonder why it differs(Regres=2.19, BezNazwy=2.18).

Antidelta(2.32) was created because the authors were dis-satisfied with aggressiveness of Delta(1.8). Difficult to see that opps.' is considered important for this.
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#20 User is offline   hrothgar 

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Posted 2006-November-24, 10:44

csdenmark, on Nov 24 2006, 06:58 PM, said:

hrothgar, on Nov 24 2006, 04:35 PM, said:

>In my book by Slawinski/Ruminski "Introduction to weak opening systems" they
>are operating with a term called 'aggressiveness'. Anybody who knows what that
>term means?

The mean opening for a bidding system descibes the expected bidding level for the opening structure.  Each opening bid in the system is represented by two numbers.

1.  The number of steps of bidding space used (Pass = , 1 = 1, 1 = 2, ...)
2.  The frequency of the opening bid.  (pass occurs on 32% of all hands, 1 on 15% of all hands, 1 on 11% of all hands, ...)

Multiply the frequency of any opening by the number of steps of bidding space and sum across all openings.  If one assumes that all preemptive openings are equally difficult to defend against the metric provides a decent description of the preemptive effect of the bidding system.

Sorry Richard I dont understand much of that.

I'll try to give you a very simple example.

Lets assume that you play a very simple system that only used 4 opening bids.

30% of all hands that you get dealt are suitable for a Pass
20% of all hands that you get dealt are opened 1
10% of all hands that you get dalt at opened 1
30% of all hands that you get dealt are opened 2
10% of all hands that you get dealt are opened 2NT

The average open level for the system can be calcualted as follows

Pass used zero stepss of bidding space
1 uses 1 step of bidding space
1 uses 2 steps of bidding space
2 uses 7 steps of bidding space
2N uses 10 steps of bidding space

The average opening level =

.3 * 0 +
.2 * 1 +
.1 * 2 +
.3 * 7 +
.1 * 10

= .2 + .2 + 2.1 + 1 = 3.6
Alderaan delenda est
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