[Chamaco]

mike777, on Aug 9 2005, 10:31 PM, said:

1nt=2d
2h=4h
p

Ditto, I'd bid like Mike even in a 15-17 framework.

4441 and 5431 (no 54 major) with stiff honor are often better described as balanced.

[kgr]

[P_Marlowe]

helene_t, on Aug 10 2005, 03:54 AM, said:

P_Marlowe, on Aug 10 2005, 10:36 AM, said:

(*) People, who claim that the weak jumb shifts  have a higher
frequency than the strong jumb shifts and also play, that the
weak jumb shift shows the range 2-6, have no clue about the
mathematics.

Depends how you define your strong jump shifts. Dutch beginners learn 12+ with a decent 6-card. That's quite frequent. My English beginner's book define it as 16+ and a suit playable opposite a void. That's different. Don't think it has much to do with mathematics, btw. I'm a mathematician and I would not volunteer to write a formula for such probabilities. I would rather make simulations or analysis of tournament records.

Hi,

right.

If you add 2 suiter, with support for openers suit
and strong NT type hands, i.e. play something ala
Soloway Jumb shifts, you will easily match the freq.
of weak jumb shifts with only 2-6 HCP.

With kind regards
Marlowe

[flytoox]

kgr, on Aug 10 2005, 09:47 AM, said:

1D-1H
2C-2S
3NT-4NT
..Is 4NT quantitative?
We play 4C gerber and 4NT RKC. Because of the wide range that opener can have (14-17) it seems very useful to play 4NT quantitative here. Most logic after 3NT would be:
- 4C/4D: fit and forcing (looking for slam)
- 4H: 6-card and strong. Interested in slam if opener still as some extras.
- 4S: Ace asking (or RKC for hearts, because other fits you can set via 4C/4D)
- 4NT: quantitative.
==> The problem is: How to make sure your partner has the same ideas about these bids. Any rules (easy and good ) you can put on paper for your partnership to define when 4NT is quantitative or RKC?

I think this is the best sequence. After 2S, opener should jump to 3N to show extra. After 3N, I think responder can rebid 4D. Opener now can bid 4H. I dont think I can find slam finally. This is a difficult one.

[Chamaco]

P_Marlowe, on Aug 10 2005, 08:36 AM, said:

(*) People, who claim that the weak jumb shifts  have a higher
frequency than the strong jumb shifts and also play, that the
weak jumb shift shows the range 2-6, have no clue about the
mathematics.

If weak = 0-6 hcp, then I wholeheartedly agree.

I agreed to play wjs = 0-6 for about 2 years and it came up only twice, whereas hands suitable for strong jumpshifts came up about 15 times.

And it's a myth that "if you have a hand suitable for SJS, you can bid them slowly", because you have a hard time to describe your honor concentration.

The power of SJS is to be able to set trumps immediately, below the level of game: if you start slowly, your pard will always "refuse" your offer to play there, and you'll reach game without being able to check for side controls.

Since when we adopted SJS, our slam biding has improved dramatically, without losing much on the 0-6 wjs.

Things would be more shaded is the jumpshift was slightly stronger (say 4-8/9 hcp), but then it would easy to bid these hands going slowly...

[P_Marlowe]

kgr, on Aug 10 2005, 04:47 AM, said:

My bidding:
1D-1H
2C-2S
3NT-??
2S: 4th suit forcing (not GF!), limit hand.

Questions:
- Most seem to play 2S as GF. Is that more standard and is it better?

Hi,

playing FSF as GF is easier, altough you still
need to discuss, what you do, with the inv.
hands.

playing FSF as INV+ is better but also mor complicate
and you need more partnership discussion, to
understand what certain bids mean, e.g. raising
the 4th suit.

Playing FSF as GF, it makes sense to play the raise of
the 4th suit as natural, not promising any extras, playing
FSF as inv+, well ... if opener is minimum and responder
as well, things will get interesting on the 4 level, if opponents
know how to use the red card.

With kind regards
Marlowe

[ochinko]

Agree completely with you and Helene. Picking between WJS and SJS is a matter of style, I don't believe it can be proved mathematically that one is better than the other. My preference is for the weak jump not because I believe it comes more often, but because of its preemptive value.

Gerben42, on Aug 10 2005, 12:23 PM, said:

One of them is that 3♥ is GF in the auction 1♦ - 1♥ - (not 1NT) - 3♥. Another big one is the same auction but responder rebids 2♥. This is invitational.

This I play differently, though. After 1♦ - 1♥ all heart rebids by the opener show exactly four hearts, but we bid upon our LTC here:
2♥ - 7 losers
3♥ - 6
4♥ - 5
No invitations. We just bid what we have, and give partner the opportunity to make an informed decision.

Petko

[coyot]

Chamaco, on Aug 10 2005, 05:36 AM, said:

P_Marlowe, on Aug 10 2005, 08:36 AM, said:

(*) People, who claim that the weak jumb shifts  have a higher
frequency than the strong jumb shifts and also play, that the
weak jumb shift shows the range 2-6, have no clue about the
mathematics.

If weak = 0-6 hcp, then I wholeheartedly agree.

I agreed to play wjs = 0-6 for about 2 years and it came up only twice, ehereas hands suitable for strong jumpshifts came up about 15 times.

And it's a myth that "if you have a hand suitable for SJS, you can bid them slowly", because you have a hard time to describe your honor concentration.

The power of SJS is to be able to set trumps immediately, below the level of game: if you start slowly, your pard will always "refuse" your offer to play there, and you'll reach game without being able to check for side controls.

Since when we adopted SJS, our slam biding has improved dramatically, without losing much on the 0-6 wjs.

Things would be more shaded is the jumpshift was slightly stronger (say 4-8/9 hcp), but then it would easy to bid these hands going slowly...

I happen to have some clue about mathematics.

Odds for a 0-6 hand are 20.56%. (2-6 18%)

Odds for a 12+ hand are 26%.

This might seem to speak in favour of strong jump shifts, BUT:
The odds that you get 12+ hand opposite a partner that already opened bidding are much lower, as this is conditional probability.

The only way to calculate it correctly would be to determine the probabilities for 12+ hand against all possible strengths for opening, as for each opener's extra point, the probability of 12+ decreases since there are less HCP to divide.

The point that seems to speak in favor of WJS is:

SJS happen only when your partnership has 24+HCP (17% of hands)

WJS happen when your partnership has 12-25 HCP (cca 80% of hands!)

The probability difference between WJS and SJS hand (generic probability above) is about 6%, but the theoretical range space in which WJS can occur is at least 4 times bigger!

The conditional probability involved may change things, but I doubt that the chance will be of the similar order. If WJS does not happen to you too often, bad luck .

Anyone care to do the real math? What are the odds for getting 12+HCP out of 28 remaining for three hands? (and 27... and 21)?

(Or a real big simulation, I don't have the proper tools).

I would bet a good sum of money on WJS coming more often :-).

[Chamaco]

ochinko, on Aug 10 2005, 11:13 AM, said:

My preference is for the weak jump not because I believe it comes more often, but because of its preemptive value.

In estimating the cost/benefit of a bidding treatment, you cannot ignore the frequency of occurrence.

The cost-benefit should be more or less (in a somwhat implified manner- I do not mean to be superscientific here)

benefit = (frequency of wins) x (average amount of wins- either in MP or IMPS, according to score)

cost = (frequency of losses) X (average amount of losses)

Therefore, it is vital to assess the frequency of occurrence of the hand type: if you use the WJS for hands that never come up, then it is a wasted bid.

[helene_t]

The silence of the opps makes your strong hand more likely, especially after a second seat opening (unless playing Precision in which case some opps might have the policy of passing strong hands and overcalling with weak hanss after your p opened 1♣).

Style can change the odds a lot, but generally it's probably safe to say that a SJS must be more diciplined (in terms of not having a side suit etc) than WJS.

I prefer WJS because it's easier. You don't have to agree on a rebid scheme (control showing? Fast arrival?). Opener just passes or raises.

[Chamaco]

coyot, on Aug 10 2005, 11:24 AM, said:

I would bet a good sum of money on WJS coming more often :-).

Well, if you had held the same hands I held in the last 4 years, you would have lost your bet, and I played on average 100 hands a week.

I used to play too WJS for nonconstructive hands for about 2 years exactly for the reason you mentioned: the textbooks advertising WJS claimed the same points.

But I surrendered to the fact that, in real life, WJS almost never came up.

SJS, on the other hands, proved to work great at IMPS, where slams matter much more than at pair

=================================

I have to say that *after opps overcalls/doubles*, there there is much more point to use WJS.
This TOTALLY different than the case of opps silent, because when your opps are silnt, the chance of slam are higher, so the best tools for slam (SJS) should be preserved.

[coyot]

See the above... WJS definitely has significantly higher probability (my guess would be a number between 2 and 3). The harder part would be determining the wins/losses.

How many slams would you miss because you could not establish trump suit at 2nd level? (Usually you establish it on 3rd level in those cases)

Honestly, I don't know.

I play WJS because I like to preempt :-) (apart from believing in the higher occurence).

WJS has it's beauty. Against weak hands, it shuts out the opponents quickly. Against stronger hands, it warns partner. I have been playing WJS for 4 years and do not recall a significant disaster (some must have happened, but nothing big).

It will be in fact impossible to establish the costs/gains properly. It is easy to compare two ways to bid an identical hand, but impossible to compare two hands bid with identical bid

[Chamaco]

Quote

See the above... WJS definitely has significantly higher probability (my guess would be a number between 2 and 3).

Perhaps, in theory, I don't know...
But in practice, are you really sure ?
I agree that it makes sense to use wjs *after opps overcall*, but -honestly -how many times was it useful to you *when opps were silent* ?

I also like to preempt, but I found out that the frequency was too low, mostly because too many hands were TOO STRONG for a wjs (= using a wjs with those hands would have resulted in preempting a strong pard rather than preempting opps).

coyot, on Aug 10 2005, 11:35 AM, said:

How many slams would you miss because you could not establish trump suit at 2nd level? (Usually you establish it on 3rd level in those cases)

NOT using SJS, it is not true that usually you set trumps at the 3-level: when you DO have a SJS hand, pard is often short in that suit and refuses to support you below 3NT.

The usual mechanics is the following.
Define SJS = 5-5.5 losers hand with self sufficient suit, not merely 17+ hcp.

Say you hold

AKQJxxxx-void -xx-xxx

You do not play SJS.
If you could, you would like to set trumps, and then verify via cuebids the controls in the minor suits, and finally use EKB

1D-1S (1)
2C-2H (2)
2NT-3S (3)
3NT- ??


1- I have time to set trump (!?!?!?)

2- I need 4sf cos 2S and 3S are both NF

3-now I have tld pard that I have long spades, but he does not know I have a selfsufficient suit. I would have bid the same even with AJxxxx-xx-Ax-Kxx, and this is wrong, wrong wrong, to bid the ame way these totally different hands

4- Now what do I bid ? Ideally I would have liked to check side controls and use EKB, but now I am stuck

====

Using SJS, you just set trumps, then use serious 3NT, cues, and RKCB/EKB to find the small/grand slam.
Quite a few times we were able to bid a grand thanks to the ability to set trumops early in the bidding (something that 4sf auction do not allow)
============================

[P_Marlowe]

coyot, on Aug 10 2005, 06:35 AM, said:

See the above... WJS definitely has significantly higher probability (my guess would be a number between 2 and 3). The harder part would be determining the wins/losses.

How many slams would you miss because you could not establish trump suit at 2nd level? (Usually you establish it on 3rd level in those cases)

Honestly, I don't know.

I play WJS because I like to preempt :-) (apart from believing in the higher occurence).

WJS has it's beauty. Against weak hands, it shuts out the opponents quickly. Against stronger hands, it warns partner. I have been playing WJS for 4 years and do not recall a significant disaster (some must have happened, but nothing big).

It will be in fact impossible to establish the costs/gains properly. It is easy to compare two ways to bid an identical hand, but impossible to compare two hands bid with identical bid

Hi,

for what's it worth, just my thought.

Assume for sake of simplicity, that an average opener shows
13 HCP. The following argument gets stronger if you open light,
and weaker, if you open conservative.

There are 27HCP out for 3 players => Average expectation for
a hand is therefore 9HCP.

Both weak and strong jumb shifts contain a 6 card suit, i.e the
probability for the hand pattern is the same, if honours are contained
in the hand, they should be in the suit.

Now with 0-6 HCP hands you are on avg. -3/4 from the avg. value 9,
with strong jumb shifts you are +3/4, a hand with 12/13 HCP and a
strong 6 carder is sufficient.

The distribution is not symmertric, i.e. -3/4 is more likley than +3/4,
but the flaw gets compensated by the other hand types, which are
included in the strong jumb shifts.

Do you still hold the wager?

With kind regards
Marlowe

PS: The above mathematical arguement is crude and an approximation,
but I am pretty sure, that the final conclusion is correct.

[Gerben42]

Quote

2- I need 4sf cos 2S and 3S are both NF

A common misconception. The whole point is that 3♠ here is forcing.
Please read my previous post again.

The relevant range for a WJS is not 0 - 6 but 4 - 8 or so.

[Chamaco]

Gerben42, on Aug 10 2005, 12:03 PM, said:

Quote

2- I need 4sf cos 2S and 3S are both NF

A common misconception. The whole point is that 3♠ here is forcing.
Please read my previous post again.

The relevant range for a WJS is not 0 - 6 but 4 - 8 or so.

The relevant range for a wjs cannot have 7-8 hcp (even 6 hcp is suspicious, if pard has 18/19 hcp we might miss game), according to all textbooks (see for instance, among others, Hardy's books): the reason is that we are in an unlimited opening world, and we risk preempting pard.
A weak js, in natural systems DENIES ANY WILLINGNESS OF CONSTRUCTIVE AUCTIONS, unless there is fit. t shows a hand worse than a 3-level preempt.
You can indeed use up to 8 hcp, but only in a limited opening world (strong club etc), because you do not risk preempting pard.



I know how you play wjs, Gerben, but it is not standard, at least neither in 2/1 nor SAYC, nor (for what it matters) in the italian 4 and 5-card major systems.
(in other words, you need special agreements)

In these standard, 3S is invitational: then if you use your approach, you need another way to show invitational hands (which I do not fancy), and/or Bourke relays and/or other gadgets, which I personally do not like.
The standard requirement for weak js is a hand without Aces and at most 6 hcp (for many, it wd be 0-5 hcp); the invitational hand should be 9/10+; in this scheme it becomes cumbersome to show the constructive hands with 7/9 hcp, too good to preempt and too weak to invite.

IMO, adopting the scheme you play into a natural system only gets things overcomplicated just for the sake of keeping a wjs bid that never comes up.
I think it makes some sense in a strong club system (when you can use wjs with 0-7/8 hcp without preempting pard), but less so in an unlimited system.

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

Also keep in mind that I am advocating giving up wjs only in UNCONTESTED auctions, and such auctions are more likely to be OUR hand, so the need to preempt is less.
In contested auctions, wjs is perfectly ok from my perspective.

But, if we restrict this discussion only on uncontested auctions, the frequency of occurrence of wjs (with aceless 0-6 hcp) vs sjs will shrink even further.

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

I know your approach is playable, yet I think that - outside of strong club/limited opening world - giving up wjs is not bad, because they do not come up often (opener being unlimited, with hands too strong for a wjs you would risk preempting him, not opps), so it's not a big loss.

In a strong club world, you can use wjs with slightly stronger hands (opener is limited, no risk of preempting him), so they come up more frequently, so it's a different issue, and I would be more keen to use them in that case.

[EricK]

It seems that there are two style for WJS

1) purely pre-emptive, probably fewer HCP than a minimum 1 level response.

2) the kind of hand which would bid 1M but then try to sign off in 2M unless opener showed significant extras.

I don't like choice 1, and would much rather play SJS. There just doesn't seem to be enough room to describe all your other hand types without making "nothing" bids (i.e. generalised forcing bids which don't tell partner anything useful about your hand).

Choice 2 is OK though. Probably just as useful as SJS and just as common.

Eric

[ochinko]

EricK, on Aug 10 2005, 03:43 PM, said:

2) the kind of hand which would bid 1M but then try to sign off in 2M unless opener showed significant extras.

This makes no sense to me. You choose to bid the same thing in two different ways, thereby getting rid both of WJS and SJS.

Petko

[EricK]

ochinko, on Aug 10 2005, 01:03 PM, said:

EricK, on Aug 10 2005, 03:43 PM, said:

2) the kind of hand which would bid 1M but then try to sign off in 2M unless opener showed significant extras.

This makes no sense to me. You choose to bid the same thing in two different ways, thereby getting rid both of WJS and SJS.

Petko

If you play WJS this way then bidding 1M and then rebidding 2M now shows the invitational strength hand.

Eric

[FrancesHinden]

Chamaco, on Aug 10 2005, 07:07 AM, said:

The relevant range for a wjs cannot have 7-8 hcp (even 6 hcp is suspicious, if pard has 18/19 hcp we might miss game), according to all textbooks (see for instance, among others, Hardy's books): the reason is that we are in an unlimited opening world, and we risk preempting pard.
A weak js, in natural systems DENIES ANY WILLINGNESS OF CONSTRUCTIVE AUCTIONS, unless there is fit. t shows a hand worse than a 3-level preempt.
You can indeed use up to 8 hcp, but only in a limited opening world (strong club etc), because you do not risk preempting pard.

Just because you put it in bold type and underline it, doesn't make it true.

Everybody I know in my country (England) who plays weak jump shifts (they aren't that common here) uses them as a constructive tool. In fact, your argument about pre-empting partner is exactly why we play them as roughly 4-8 HCP and constructive. You jump in a suit to show a well-defined hand. Whether your definition is 0-5 or 4-8 doesn't change that fact that you have described your hand very well to partner, who now can make an informed decision.

I'm probably just going to repeat what Gerben said, but let me explain why so many people play the WJS as constructive. Define a 2-level jump response to partner's 1-of-a-minor opening as

3-7 HCP with a 7-card suit, 4-8 with a 6-card suit, depending a little on vulnerability, suit quality and level of fit for partner's suit (e.g. Kxxxxx x QJx xxx is often a 1S response to 1D becaue you could easily want to play in diamonds; KJ109xx x xxx xxx is a 2S response at all vulnerabilities).

Now you have three superb new constructive weapons:
i) 1m - 1M - 2 either m - 2M shows an invitational hand with 6 cards (about 9-12) and allows you to play at the 2-level on a misfit, or to investigate the best game at a sensible level. Standard bidding has no good way to show this hand (you have to overbid or underbid).
ii) 1m - 1M - 2 either m - 3M is game forcing with a good suit. This replaces some of the strong jump shift hands you have lost, though it doesn't have to be quite SJS strength.
iii) Responder has defined their hand well when she makes a WJS, so opener can make an informed decision. With 18-19 balanced for example, opener just bids game. Some people play system after a WJS - you could play exactly what you play in response to a weak two such as an Ogust 2NT enquiry. We play step 1 as a shortage ask (followed by step 1 as a trump quality ask for slam purposes).

Plus you have put in a mild pre-empt.

Alternatively, you could play the WJS as 0-5. I agree that this is a more common American treatment, and the constructive version seems to be more common in England. Personally I can see no advantage in this treatment because
i) 0-5 with a 6-card suit is (I think) less common than 4-8 with a 6-card suit, so the pre-emptive impact is less common
ii) You have removed one constructive call (the SJS) from your system, but not replaced it with anything, so your constructive auctions have to cover just as many hand types as before with fewer calls.

There must be some reason to play them this way - very weak - because so many people seem to do so. So I'm not going to say in bold, and underlined, that you cannot play it your way. But I'd rather play SJS.