Bridge Thoughts

Minor Suit Raises

2011-02-25T20:33:00.000-08:00

Most top pairs now play "inverted" minor raises. Using this method, a double raise is weak and a single raise is a one round force with invitational values or better. However I prefer the single raise to have its traditional meaning: four card support and about 5-9 HCP.

Suppose partner opens 1♦ and you have a hand such as:

Kxx

Qxxx

Q10xx

It is a bit much to jump to three diamonds with no shape and partner possibly having only three diamonds, so, playing inverted raises, this hand would probably respond 1NT. There are two important reasons that a 2♦ response is likely to work out better.

The first is that the 1NT response is likely to lead to any notrump contract being played from the wrong side. Maybe the two hands are something like this:

Q10x	Kxx
AQx	xx
AKxx	Qxxx
KJx	Q10xx

There is a much better chance of making 3NT when played by the West hand. Since the 1NT response with four card support will be made on a weak hand with no four card major it is quite likely that the hand will lack good stoppers in the majors and a NT contract will play better from the other side after an auction such as 1♦-2♦-3NT.

The second reason to bid 2♦ is that supporting immediately allows partner to compete when it is correct to do so. Maybe the full hand is something like this:

	J10xx
	109x
	Kx
	98xx
xx		Kxx
AQxx		xx
AJ10xx		Qxxx
Kx		Q10xx
	AQxx
	KJxx
	xx
	AJx

South will double the 2♦ response and West can bid an immediate 3♦. This may or may not shut out the opponents, but you are assured of a plus score since 3♦ makes and 3♠ is down at least one. If South had responded 1NT instead, South would double. It isn’t really safe for West to bid 2♦ because partner could easily be 3325 and with the doubler likely short in diamonds as well it could get very messy. So when West passes and North bids 2♠, East has to guess whether to compete to 3♦. Maybe the full hand is:

	J10xx
	109x
	KJxx
	xx
xxx		Kxx
AQxx		xx
A10xx		Qxxx
Kx		Q10xx
	AQx
	KJxx
	x
	AJ98x

You will probably be down two doubled in 3♦ and the opponents’ 2♠ may not make either. If you play a weak notrump West will not have that hand, however if the king and ten of diamonds are switched West will have a 1♦ opening and both 2♠ and 3♦ are still down.

There is plenty of space to handle stronger hands with support for partner’s minor because we can use jump responses. Traditional strong jump shifts don’t occur very often and weak jump shifts have little advantage over just bidding and rebidding the major suit.

I recommend the following structure over a 1♦ opening:

2♦	Four card support and about 5-9 HCP
2♥	Five spades and four hearts with about 7-9 HCP
2♠	Four card or better support and about 10+ HCP
2NT	16+ balanced
3♣	Five card support and about 7-8 HCP
3♦	Five card support and 4-6 HCP

I like to use the 2♥ response for a hand such as Axxxx KJxx xx xx because otherwise a 1♠ response and 2♦ rebid from partner will make life difficult. Partner could have either of the following hands:

x	x
AQxx	xxx
AKxxxx	KQJxxx
xx	AKx

Opposite the first hand I want to be in four hearts. Opposite the second I would prefer to be in 2♦ but can live with playing 2♥ or 3♦. But after a forcing and unlimited 2♥ rebid partner really has to drive to game with the second hand. There is also a possibility that partner could have 1444 shape and we can make 9 or 10 tricks in hearts but could be playing 2♦ if I respond 1♠ and partner rebids 2♣.

I also like to have a bid for strong balanced hands as these are hard to describe accurately, for example:

xx		Kx		AQxx
Ax	or	Ax	opposite	Kxxx
KQxxx		KQxxx		Ax
Axxx		Axxx		KJx

After 1♦-1♥-2♣, East would like to stop in 3NT opposite the first hand but 6NT has good play opposite the second. Fourth suit forcing can be used but this tends to show doubt about strain, rather than necessarily extra values. Responding 2NT with 16+ balanced solves this problem and a natural 2NT response is not really needed as we can respond either 2♣ or 2♠ with those hands. I don’t recommend that you play 1♦-2♣ as forcing to game even if you normally play that a two over one is game forcing.

We also have two ways to show five card support. Since we are already at the three level with no space to investigate further without going past 3♦, it makes sense to have narrower ranges in case partner is considering bidding on.

All of this does mean that our forcing raise is two steps higher. However there is still plenty of space to investigate stoppers below 3NT.

If the opening bid is 1♣, you can do the same one step lower or rearrange things a little if you prefer, e.g.

2♣	Four card support and about 5-9 HCP
2♦	Four card or better support and about 10+ HCP
2♥	Five spades and four hearts with about 7-9 HCP
2♠	Five card support and about 7-8 HCP
2NT	16+ balanced
3♣	Five card support and 4-6 HCP

A final point is that a single raise, 1♣-2♣ or 1♦-2♦, does not deny a four card major. Though you will often respond in a major, there are considerable tactical advantages in bypassing a major to raise partner’s minor, especially when the major is hearts. If your side has a 4-4 heart fit and you have support for partner’s minor suit, there is a good chance the opponents can make a spade contract. Maybe they can still find it if you raise, but your LHO opponent may not be willing to overcall at the two level, or may have a hand that cannot double for takeout due to short hearts, for example:

	Jxxx
	Axx
	Jxx
	Q10x
Q10x		xx
KJxx		Q10xx
AKxx		Qxxx
xx		Kxx
	AKxx
	xx
	xx
	AJxxx

East-West can make eight tricks in either red suit, while North-South can make nine in either black suit. If East responds 1♥ to West’s 1♦, South will double and North-South will go plus in a spade contract or defending 3♥. If East instead raises to 2♦, it may go all pass. East-West will certainly not be upset to score 90 in 2♦ instead of 110 in 2♥.

The Compound Squeeze

2011-01-14T15:02:00.000-08:00

I have recently read the 2010 edition of 'Bridge Squeezes Complete' by Clyde Love. Love died over 50 years ago and the latest edition was updated by Linda Lee and Julian Pottage. The highlight for me was the section on compound squeezes. The book devotes 72 pages to them, compared to close to zero pages in other books I've seen. The example below is mine, not from the book:

		♠	x x x
		♥	K x x
		♦	x x x
		♣	A K Q x

		♠	A K Q J x x
		♥	A x x
		♦	A x
		♣	x x

Let's say you reach 6NT at matchpoints and receive the jack of clubs lead. Obviously you have 12 tricks and would like to make an overtrick. Before reading the book, my first reaction would be that I need someone to have five hearts and four clubs, or they may discard badly and expose themselves to a double squeeze. In fact, thirteen tricks can always be made when West has four or more clubs. Let's take a typical layout where both opponents control both red suits:

		♠	x x x
		♥	K x x
		♦	x x x
		♣	A K Q x
♠	x x			♠	x x
♥	Q 10 x			♥	J 9 x x
♦	K 10 x x			♦	Q J x x
♣	J 10 9 x			♣	x x
		♠	A K Q J x x
		♥	A x x
		♦	A x
		♣	x x

You win the club and play off five rounds of spades. West can afford two diamonds but on the fifth spade he must leave his partner in sole control of either hearts or diamonds. You can then cash the top card(s) in the suit now guarded solely by East and complete a double squeeze by playing the last spade. If West unguarded hearts, then diamonds will be the pivot suit for the double squeeze and if he unguarded diamonds then hearts will be the pivot suit.

You do need to read the position. If West sees what is coming he should let go a heart early so he can discard his second diamond at the crucial moment. You may then choose to play West for 2434 instead of 2344. Then the squeeze will fail and you will be held to 12 tricks.

This is not a particularly unusual situation since it doesn't depend on the precise location of the cards to any great extent. I expect compound squeezes come up much more often than people notice.

Bermuda Bowl Analysis

2009-09-15T00:18:00.000-07:00

I have done some analysis on the performance of each pair in the Bermuda Bowl final.

The method is based on assigning each pair an IMP score on each board reflecting the result they deserve to get relative to an error-free world class pair. In most cases I did this independently of the actual result so a minus would be assigned for missing a good game regardless of whether the game made in practice.

There is also a luck score for each board which is not assigned directly and is just the difference between the accumulated 'deserved' IMPs and the actual IMPs that changed hands. The total of this over the 128 boards was only 6 IMPs (in favour of the USA) so luck had very little effect overall though there were big numbers on individual hands.

Here is an example of the methodology. On board 2, Lauria/Versace were -200 in 4C and Nickell/Katz were -100 in 3NT. Based on the N/S cards I judged that 4C will normally make and 3NT will be down one. However, on the actual lie 4C is down one (though it can make double dummy) and 3NT is down two. Accordingly I penalized Lauria/Versace 3 IMPs for an unnecessary extra undertrick, Nickell/Katz 6 IMPS as they 'deserved' -100 against +130, and Fantoni/Nunes 3 IMPs for letting Nickell/Katz get out for -100 instead of -200. Since the USA gained 3 IMPs and the deserved IMPS totalled zero, this counted as 3 IMPs in the luck column for the USA. The luck here is in the fact that an unusually bad lie converted a possible partscore swing against the USA into just a question of undertricks.

The totals were:

Pair	Num Boards	Avg. IMPs per board
Meckstroth/Rodwell	128	-1.15
Hamman/Zia	80	-1.59
Nickell/Katz	48	-2.10
Lauria/Versace	96	-1.50
Fantoni/Nunes	80	-1.21
Sementa/Dubion	80	-1.95

As you can see, Meckstroth/Rodwell did slightly better than Fantoni/Nunes, while Lauria/Versace did slightly better than Hamman/Zia. Nickell/Katz and Sementa/Dubion were easily the weakest pairs on their respective teams.

It appears that the choice of lineups accounts for almost the entire winning margin. The US played their best pair for every board and their weakest pair for the minimium number. If Italy had done the same, by my reckoning they would have closed the gap from 36 IMPs to 7 IMPs - less than the carryover.

The calculations are in this Excel spreadsheet. I am certainly open to any of this being disputed as there may be excellent reasons for the bids and plays chosen that I am unaware of.

The play records are located here.

The Case for the Weak NT: Summary

2009-09-15T00:01:00.002-07:00

So far we have seen:

Both the weak and strong notrump carry negative inferences that are useful after opening one of a suit. However, because the weak notrump includes all of the weakest playing strength opening hands, it has the effect of increasing the lower limit of your other one level openings. This is a big plus.

The strong notrump leads to awkward rebid problems on unbalanced hands in the 15-17 range. This is less of a problem with the weak notrump as the suit opened can be rebid with a minimum opening and 1NT is available with a better hand.

Missing a 4-4 major fit is a possible disadvantage for the weak notrump, but this happens much less often than is commonly believed and need not always lead to a bad result even when it does occur.

The side that opens 1NT is much better placed in the subsequent auction. A weak notrump means this advantage is enjoyed more often. A weak notrump opening also means the opponents need to consider whether they have a game or can extract a penalty, in addition to just locating their best partscore. All of this in the very limited space available to them when you have started with 1NT.

Finally, a computer analysis of the likelihood of being doubled for a penalty after opening 1NT shows you can expect a 10 IMP loss once every 800 hands, under assumptions very favourable to the opponents. Under more realistic assumptions, the loss is probably miniscule or non-existent.

I would like to conclude by pointing out that the weak notrump works just as well with a five card major system and 2/1 game force as it does with Acol or similar systems. Do try it!

The Case for the Weak NT: Going for a Number

2009-09-15T00:01:00.001-07:00

Nobody likes to get doubled and concede a big penalty. There will be times when this happens and you get a bad result that could only have been avoided by not playing a weak notrump in the first place. The question is how often this happens and whether the cost outweighs the benefits described in the previous three sections. I've done some computer analysis on this, using the following assumptions:

- Your weak 1NT opening is in first position at any vulnerability.
- An unpassed opponent will double your 1NT if and only if he has 15 or more HCP.
- A passed opponent will double your 1NT if he has a decent single suited hand (DONT).
- If RHO has a double, LHO never bids in front of him.
- When 1NT is doubled you will always run to a suit contract.
- You always end up in two of your best fit. With good runout methods you can usually achieve this.
- After you run, opponents always make the optimum double dummy decision, i.e. doubling you if and only if the penalty they can get exceeds what they could score in their own best contract.
- The scoring is IMPS and the theoretical par contract is achieved at the other table

These assumptions are very favourable to the opponents of the weak notrump bidder. In reality, there are all kinds of things that may go wrong for them:

- They may double and you make.
- They may get an inadequate penalty.
- You may have the balance of power and redouble, either making (1560 is not unheard of) or penalizing them.
- They may choose to bid or pass instead of doubling when a penalty is possible.
- Even if your doubled contract is theoretically optimum for them they may drop a trick on defence. In low level contracts, defence is harder than declarer play and opening leads are harder still.
- Similarly, even if the penalty is theoretically optimal because their game or slam fails double dummy, it might make in practice.

The results of the computer simulation are as follows, for each position of the weak notrump opener:

1st seat: 1NT opened on 8.08% of hands. An average loss of 0.22 IMPS per hand each time 1NT is opened.
2nd seat: 1NT opened on 3.65% of hands. An average loss of 0.18 IMPS per hand each time 1NT is opened.
3rd seat: 1NT opened on 1.47% of hands. An average loss of 0.45 IMPS per hand each time 1NT is opened.

Put another way, this averages out to one 10 IMP loss once every 640 hands. If you don't play the weak notrump in third seat, it's a 10 IMP loss once every 800 hands.

Remember this assumes the opponents make perfect decisions every time. They certainly won't in practice, and you'll break even or gain for all the reasons listed above. Actually, after adding back in the times you get +180 or they have some other kind of accident, you may well end up showing a profit even on the hands where doubling is an option for them. This is added, of course, to the gains in all the situations discussed under the other headings.

The Case for the Weak NT: Advantages of opening 1NT generally

2009-09-11T17:49:00.000-07:00

The limited strength and distribution of a 1NT opening allows auctions that are less revealing to opponents compared to opening one of a minor. The contracts reached after a 1NT opening are therefore more likely to make. You'd rather bid 1NT-3NT than 1D-1S-1NT-3NT because you have a better chance of a favourable opening lead and the subsequent defence will be more difficult as well.

The weak notrump occurs more often so it gains the most from this.

When the hand belongs to the opponents, it is more difficult and dangerous for them to enter the auction when you open 1NT, compared to opening one of a minor:

They have to start bidding at the two level
They have the additional objective of trying to get a penalty, not just bidding to their own best contract
If they pass with a decent hand, there may well be no second opportunity
Whether your partner passes or bids, there is still no safety for them as your side can have almost game values and no fit
The limited shape and strength of the 1NT opener makes it easier for you to judge when to double them
The 1NT opener has not shown a suit so takeout doubles and cue bids are not available for them
Auctions over opponents 1NT are generally not discussed and understood as well as auctions over their suit opening.

Over a strong notrump, finding your best partscore is the overriding objective and methods can be tailored just to do that. Defences such as DONT, Meckwell and Lionel are all designed to do this but you'll find it hard to extract a penalty or bid constructively towards game if you try using these against a weak notrump.

There's no real solution to this - bidding accurately over an opponent's weak notrump is just extremely difficult. Here are a couple of examples:

♠	xx		♠	xx		♠	KQxx
♥	KQJ10xx	or	♥	KQJ10xx	opposite	♥	xx
♦	Qxx		♦	AQx		♦	Kxx
♣	xx		♣	xx		♣	Axxx

If West has the first hand, 1NT could well make if he passes and 3H is too high if he bids and partner invites. On the second hand, E/W have a game in hearts. After a 1C opening, both hands are easy to bid depending on whether your jump overcalls are weak or intermediate. Starting a level higher after a 1NT opening, there isn't enough space to do everything.

♠	AQxx		♠	Kxxxx		♠	xx
♥	x	opposite	♥	Qxxx	or	♥	QJxxx
♦	KJxxx		♦	Qx		♦	xx
♣	Qxx		♣	Kx		♣	Kxxx

Let's say E/W have a bid showing spades and another suit. West will be reluctant to bid over 1NT, especially vulnerable, in case East has the second hand and he concedes a significant penalty against a part score. Of course, if East has the first hand he will miss an easy game. There is no such problem after a minor suit opening.

♠	AQxx		♠	Kxx		♠	xxx
♥	KJx	opposite	♥	Qxxx	or	♥	xxxx
♦	AQJx		♦	xx		♦	xx
♣	xx		♣	QJxx		♣	QJxx

If West doubles, his partner with the second hand will have no choice but to pass and concede something like 380 (or 960 if they redouble). Obviously if he passes and partner has the first hand, E/W will miss either a game or a sizeable penalty. If West doubles a 1C opening for takeout opposite the second hand, E/W will get no higher than 1H or 1S, probably down one undoubled.

The Case for the Weak NT: Playing the wrong partscore

2009-09-10T00:52:00.000-07:00

After a 1NT opening there is always a risk of a missing a 4-4 major fit on a partscore hand. The weak notrump occurs with greater frequency which makes this more likely and also the extra strength of the strong notrump means that 1NT will still often make when a better spot is available. To actually lose IMPs this way, though, several things have to happen:

1NT has to go down while 2 of a major is making
The opponents must remain silent over 1NT. If they bid, you can make a takeout double and still find your 4-4 fit.
The opponents must not be able to successfully outbid you. It is risky to enter the auction over 1NT, while balancing when opponents bid and raise at the two level is relatively safe. So you might never be able to play 2 of a major anyway.

About 13% of hands qualify for a weak notrump opening. On about 10% of these, responder will pass when you have a 4-4 major fit. Moderately aggressive opponents will only let you play in 1NT on about 20% of such hands. Overall, this is about one in every 770 hands, not including those where they can successfully bid over your two of a major but would pass 1NT, or where the 1NT contract does as well as, or better than, two of the major.

You can also alleviate the problem by responder using Stayman on weaker hands with 4-4 in the majors. As long as partner doesn't open 1NT with 2254 or 2263 shapes you'll play a 4-3 at worst which may still be better than 1NT. It's better to have two decent suits for this as three trumps opposite four small ones doesn't usually play well. You also need to agree that after 1NT-2C-2D-2H opener must correct to 2S holding three spades and two hearts.

There is also a corresponding situation where a 1NT opening makes it easier to locate an eight card major fit. This is where opener is balanced and responder has a five card major. After a 1NT opener, responder will transfer and pass. After a 1C/D opening and responder bids his major, opener may raise with three cards or bid 1NT. If he bids 1NT responder will pass and the eight card fit will be lost. If he raises, you'll play a 4-3 fit some of the time and the range of opener's raise is uncomfortably stretched if it may include a weak balanced hand with three card support. Playing a 5-2 when responder transfers and passes is less likely to be wrong than missing a 5-3. The extra frequency of the weak notrump is therefore a benefit on these hands. Furthermore, when 1NT is not opened, a three card raise on a balanced hand is not a stretch as opener will have 15+ HCP.

Finally, after opening one of a minor with 12-14 balanced it is not clear what is supposed to happen with a 4-4 fit when responder does not introduce the suit immediately, e.g. opener has four spades and the auction starts 1C-1H. If opener bypasses 1S and rebids 1NT, you lose spades when responder is too weak to act so are in the same position as a weak notrump opener except your two extra bids have helped the defence. If opener bids 1S instead of 1NT you risk playing 1NT from the wrong side or not at all when that is the best contract.

To summarise, opening 1NT may risk missing a 4-4 major fit on a partscore hand and the weak notrump does make this more likely. However this is much less frequent and less serious than is commonly believed, and in any case such hands will not usually end quietly in two of a major after a minor suit opening. There are other situations where a 1NT opening makes it easier to correctly find a major suit part score.

The Case for the Weak NT: Offshape 1NT openings and rebids

2009-09-08T00:44:00.001-07:00

Playing a weak notrump, there is less need to open 1NT with imperfect shape. For example:

♠	x
♥	AJxx
♦	Kxx
♣	AKJxx

Playing a weak notrump you open 1C and rebid 1NT if partner responds 1S. However, playing a strong notrump you have a real problem. The hand is not good enough to reverse but too good to rebid 2C. I suspect most experts would open 1NT if the singleton spade was an ace or king, otherwise open 1C and either 'upgrade' to a reverse or 'downgrade' to a 2C rebid. This is unsatisfactory as there is a significant gap between the upper limit of a simple rebid of the suit opened and the lower limit of a reverse. I suppose you could also try a 3C rebid on a five card suit but that is a significant misdescription.

Opening 1NT leaves you poorly placed if partner is weak with five spades (he'll transfer and pass) or when he has four hearts, e.g.

♠	xxx
♥	KQxx
♦	xxx
♣	Qxx

Or a balanced hand with no spade stop:

♠	xxx
♥	Kxx
♦	AQxx
♣	Qxx

And the worst case is good club support:

♠	Axx
♥	KQx
♦	Ax
♣	xxxxx

It would be a pity to bid 1NT-3NT when 7C is possible. Even if you only open 1NT when the singleton is an honour, a hand with the king of spades instead of the king of diamonds would do equally well in 7C. If the hands didn't fit well 6C would still often be a good contract.

After opening 1C and hearing 1NT from partner, the 1NT rebid is not ideal either but you do avoid the worst of the problems with an offshape 1NT, exemplified by the example hands above. The reverse problem does not apply with an offshape 12-14. Without the king of diamonds you would be too weak for a 15-17 1NT rebid but there is no problem as you can open 1C and rebid 2C if partner bids 1S.

There are some players who are happy to open 1NT offshape and believe they gain by doing so. If you are one of them, then you won't regard it as a disadvantage that the strong notrump forces you to do so. However, the idea that you gain by opening 1NT as often as possible is also yet another argument in favour of the weak notrump.

The Case for the Weak NT: Inferences when 1NT is not opened

2009-09-05T00:59:00.000-07:00

Balanced hands in the 12-14 range have the least playing strength of all opening hands. Therefore, the weak notrump effectively increases the minimum strength of opening bids of one club and one diamond so these have a narrower range. Conversely, the strong notrump removes intermediate range hands from the one of a minor openings. Consider the following hand:

♠	Qxx
♥	AKxx
♦	xx
♣	AKxx

LHO makes a preemptive jump to 3S over your opening bid. Partner passes. There is no problem if you opened a strong notrump as you've shown extra strength already so have no reason to bid more. It's more difficult if you opened 1C playing a weak notrump. Suppose you pass 3S. Consider three possible hands for partner:

♠	x	♠	Jx	♠	xx
♥	Qxx	♥	Qxx	♥	Qxxx
♦	Axxxx	♦	AJxxx	♦	Axxx
♣	Qxxx	♣	Qxx	♣	Qxx

The first hand gives some play for 4H or 5C though I think partner might double, rather than pass. The hand with shortness needs to take the lead in these situations. It would be nice to have a fourth heart but a 4-3 fit could be ok. Even playing a strong notrump, there are plenty of hands where you want to be in the auction but it will be hard for opener to act after a pass.

The second hand is probably close to a maximum pass. You might make 3NT but it needs some luck. Likewise the third hand is marginal for 4H and partner would double if stronger.

Examples like this suggest to me that it's acceptable to pass an average strong notrump in this situation. Also bear in mind that partner can make a negative double a bit more freely playing a weak notrump as he knows you won't have a weak balanced hand. And none of the above would be straightforward if the opening bid was a 15-17 1NT instead of 1C.

Playing a weak notrump, the inferences after a 1C/D opening occur in situations such as the following:

♠	AQJxx		♠	K10xx		♠	K10xx
♥	xxx	opposite	♥	Axx	or	♥	Ax
♦	xx		♦	AQxx		♦	AQxxx
♣	Qxx		♣	xx		♣	xx

In each case, the bidding starts 1D-1S-2S. Opposite the first hand, you cannot make game and are in danger at the three level. With the second, game is close to 50% and worth bidding at IMPs. Removing hands such as the first one by opening them with 1NT means opener's playing strength falls with a narrower range and decisions about whether to bid game are therefore more accurate. What tends to happen playing a strong notrump is that opener will stretch to bid 3S on hands not much stronger than the second, which may well lead to a hopeless contract opposite a minimum responder.

The exclusion of strong notrump hands from an opening bid of one of a minor does not carry any such useful inference as opener may still have an unbalanced hand of equivalent playing strength.

The Case for the Weak Notrump

2009-09-05T00:42:00.000-07:00

This is the introduction to a series of posts analysing the merits of a strong (15-17) notrump vs a weak (12-14) notrump. The name of this post might suggest the analysis will not be particularly objective, but the evidence is strong enough that it's hard to avoid any other conclusion.

I will assume the rest of the system is five card majors and a 2/1 game force structure, though there won't be much difference if not. The arguments for or against the weak notrump fall roughly into five categories:

I'll post on each of these over the next few days plus a summary at the end.

NZ vs Italy

2009-08-31T20:22:00.001-07:00

The following is a report of the NZ vs Italy match from the Bermuda Bowl round robin. I don't have much experience in formatting bridge hands in HTML so let me know if it doesn't look good in your browser. The relevant system cards can be located here.

The first board was a cold 3NT at both tables - no swing.

Bd: 18

♠

Dlr: E

♥

AKJ984

Vul: N/S

♦

♣

A1043

♠

K8542

♠

1097

♥

1062

♥

♦

J52

♦

A643

♣

9872

♠

AQ6

♥

♦

K10987

♣

KJ6

	NT	♠	♥	♦	♣
W	1	4	1	3	1
N	11	8	11	10	11
E	1	4	1	3	1
S	12	9	12	10	12

N	E	S	W
Cornell	Sementa	Bach	Duboin
	P	1NT	P
2♦	P	2♥	P
3♣	P	3NT	P
5♥	P	6♥	P
P	P

♠2	♠3	♠9	♠Q
♦7	♦5	♦Q	♦A
♠7	♠A	♠4	♠J
♦8	♦2	♥8	♦3
♥A	♥3	♥7	♥2
♥4	♥5	♥Q	♥6
♦9	♦J	♥J

A 13 IMP swing to NZ from a combination of judgment and systemic differences, where the systemic differences were more luck than superior methods.

6H is a good contract by South, but not by North, so the strong notrump worked better. 4H by Cornell would have been a mild slam try, as with just game values he would bid 4H over 2H. Bach would probably have passed this, but was happy to go on to slam over the more strongly invitational 5H with help in partner's long suits along with primary cards in his short suits.

Bd: 19

♠

K543

Dlr: S

♥

Q86

Vul: E/W

♦

AK105

♣

♠

J10976

♠

A82

♥

A102

♦

J64

♣

AQ632

♣

10854

♠

♥

J9753

♦

Q9832

♣

	NT	♠	♥	♦	♣
W	6	9	4	4	10
N	6	4	8	8	3
E	6	9	4	4	10
S	6	4	8	8	3

N	E	S	W
Cornell	Sementa	Bach	Duboin
		2♥	2♠
4♥	4♠	P	P
Dbl	P	P	P

♦K	♦4	♦8	♦7
♦A	♦6	♦9	♠6
♠7	♠3	♠2	♠Q
♦Q	♠9	♦5	♦J
♣A	♣J	♣4	♣7
♣2	♣K	♣T	♣9
♥Q	♥2	♥3	♥K
♠T	♠4	♠8	♥5
♣Q	♥8	♣8	♥7
♣6	♠5	♣5

N	E	S	W
Fantoni	Whibley	Nunes	Ware
		P	1♠
1NT	Dbl	2♦	P
2♥	2♠	3♦	3♠
4♥	Dbl	P	P
P

♣5	♣7	♣A	♣J
♦7	♦T	♦J	♦Q
♥3	♥4	♥Q	♥A
♦6	♦2	♥K	♦K
♣2	♣K	♣4	♣9
♥8	♥2	♥5	♠6
♥6	♥T	♥J

New Zealand is probably the most aggressive preempting team in the competition and Italy the most conservative.

On this hand Bach's threadbare 2H opening led everyone to stretch and Dubion/Sementa ended up too high in 4S, though both their actions are understandable. The contract is not bad just looking at the E/W cards, but the bidding made bad breaks likely and a forcing defence meant the contract was unmakeable. Dubion might have escaped for one down with good guessing but ended up two down for -500.

At the other table, Nunes passed and N/S took a while to find their heart fit allowing E/W to communicate their (lack of) values at a lower level. Fantoni's final 4H bid is clearly too much, though without knowing their style it's possible that Nunes's 3D was the main culprit. On a club lead and diamond switch, this might also have gone two down but Ware failed to rise with KH on the trump lead from dummy so could only ruff with the winning trump. KH would be wrong if East might double with Jxx of hearts plus AS and KC.

12 IMPS to NZ. NZ 25, Italy 0.

Bd: 20

♠

J84

Dlr: W

♥

Q1082

Vul: All

♦

Q852

♣

109

♠

K1076

♠

AQ93

♥

764

♥

♦

J10

♦

♣

8432

♣

KQJ75

♠

♥

AK93

♦

AK764

♣

	NT	♠	♥	♦	♣
W	3	8	2	3	8
N	9	5	11	10	5
E	3	8	2	3	8
S	9	5	11	10	5

N	E	S	W
Cornell	Sementa	Bach	Duboin
			P
P	1♣	1NT	P
P	P

♣3	♣T	♣J	♣A
♦4	♦T	♦Q	♦3
♦2	♦9	♦A	♦J
♦6	♥6	♦5

N	E	S	W
Fantoni	Whibley	Nunes	Ware
			P
P	1♣!	Dbl	P
1♥	P	2♣	P
2♦	P	4♥	P
P	P

♣K	♣A	♣2	♣9
♥A	♥4	♥2	♥5
♥3	♥6	♥Q	♥J
♥8	♣7	♥K	♥7
♦4	♦J	♦Q	♦3
♦2	♦9	♦A	♦T
♦K	♠6	♦5

Another combined system/judgment swing, this time to Italy. Over East's 1C opening, Bach chose a 1NT overcall which ended the auction while Nunes doubled and reached a successful 4H game.

My view is that South is both too strong and too suit-oriented for a 1NT overcall. Bids with one flaw often succeed, but with two flaws you are better off trying something else. Here the options are 1D or dbl. Heavy overcalls are not my style so I would double, though 1D is possible and would be the choice of many experts.

After the double I prefer a 3H raise to Nunes's cue bid followed by 4H. South has a good hand but with loads of space available there is no need for him to essentially bid game on his own. North's two working queens are enough continue if invited and both are needed to make game good.

10 IMPS to Italy. NZ 25, Italy 10.

Bd: 21

♠

AKJ762

Dlr: N

♥

Vul: N/S

♦

QJ5

♣

♠

♥

KJ52

♥

Q8743

♦

AK1086

♦

♣

J943

♣

K765

♠

Q10954

♥

A10

♦

974

♣

A102

	NT	♠	♥	♦	♣
W	4	4	10	8	9
N	8	9	3	5	3
E	4	4	10	8	9
S	8	9	3	5	3

N	E	S	W
Cornell	Sementa	Bach	Duboin
1♠	P	4♠	Dbl
P	5♥	Dbl	P
P	P

♠4	♥2	♠6	♠8
♦A	♦5	♦3	♦4
♦K	♦J	♦2	♦7
♦6	♦Q	♥7	♦9
♥3	♥T	♥K	♥6
♣3	♣8	♣K	♣A
♠5	♥5	♠2	♠3
♣4	♣Q	♣7	♣2
♠A	♣5	♠9	♥J
♣J	♥9

N	E	S	W
Fantoni	Whibley	Nunes	Ware
2♠!	P	4♠	P
P	P

♥3	♥A	♥2	♥6
♠T	♦6	♠A	♠3
♠7	♠8	♠9	♦8
♥T	♥K	♥9	♥8
♦K	♦5	♦2	♦4
♦A	♦J	♦3	♦7
♦T	♦Q	♣5	♦9
♣8	♣7	♣A	♣3
♣2	♣4	♣Q	♣K

NZ gained 9 IMPS when Ware judged a high level competitive auction better than Dubion. The 2S opening by Fantoni was intermediate so both Wests were in a similar position. Ware passed and collected 100 against 4S (though 200 was possible). Dubion doubled and Sementa in 5HX chose to play 'safely' for -300 rather than hope for 2-2 trumps and risk losing control. Bach also helped to create the swing with his heavy 4S jump. Unlike Nunes, he was facing an unlimited opener.

I think double is the percentage action with West, but it can obviously be wrong as it is here. East's 5H is also reasonable though passing the double is an option as well.

9 more IMPS to NZ. NZ 34, Italy 10.

Bd: 22

♠

KJ976

Dlr: E

♥

J643

Vul: E/W

♦

♣

♠

104

♠

AQ53

♥

Q1092

♥

♦

Q32

♦

AJ105

♣

10975

♣

AQJ3

♠

♥

A875

♦

K976

♣

K42

	NT	♠	♥	♦	♣
W	9	7	7	9	10
N	4	6	6	3	3
E	9	7	7	10	10
S	4	6	6	3	3

N	E	S	W
Cornell	Sementa	Bach	Duboin
	1♣	1♥	P
1♠	P	2♦	P
2♥	Dbl	P	3♣
P	P	P

♠8	♠T	♠J	♠Q
♥K	♥A	♥2	♥3
♦6	♦Q	♦4	♦5
♣5	♣6	♣A	♣2
♣3	♣4	♣T	♣8
♣7	♦8	♣Q	♣K
♠2	♠4	♠6	♠A
♠3

N	E	S	W
Fantoni	Whibley	Nunes	Ware
	1♣!	P	P
P

♠2	♠4	♠9	♠Q
♥K	♥A	♥2	♥3
♥5	♥9	♥J	♣3
♣A	♣2	♣5	♣6
♣J	♣4	♣7	♣8
♠A	♠8	♠T	♠7
♠3	♥7	♣9	♠6
♦Q	♦4	♦5	♦K
♣K	♣T	♥4	♣Q

This is a pretty good 3NT that might have been reached after an offshape 2NT opening. Both Easts, however, opened 1C and played a club partscore. I agree with the 1C opening which makes it much easier to reach a minor suit game or slam (or partscore) and the risk of missing a game is small.

Italy gained 1 IMP for an extra overtrick. NZ 34, Italy 11.

Board 23 was a routine 3NT and Italy gained another overtrick IMP. NZ 34, Italy 12.

Bd: 24

♠

Q652

Dlr: W

♥

J1065

Vul: None

♦

K984

♣

♠

K9743

♠

J10

♥

AQ2

♥

K983

♦

AQJ103

♣

9842

♣

♠

♥

♦

765

♣

AKJ1075

	NT	♠	♥	♦	♣
W	6	8	8	8	6
N	7	5	4	5	7
E	6	8	8	8	6
S	7	5	4	5	7

N	E	S	W
Cornell	Sementa	Bach	Duboin
			P
P	1♦	2♣	2♠
P	P	3♣	P
P	P

♦2	♦4	♦T	♦6
♣3	♣5	♣2	♣Q
♥5	♥3	♥7	♥Q
♥A	♥6	♥8	♥4
♣4	♠2	♣6	♣7
♣A	♣8	♠5	♦3
♣K	♣9	♦8	♦J
♣T	♠7	♥T	♥9
♣J	♠4	♥J	♠J
♠A	♠3	♠6	♠T
♠8	♠K	♠Q	♦Q
♥2	♦9	♥K	♦5
♦A	♦7	♠9	♦K

N	E	S	W
Fantoni	Whibley	Nunes	Ware
			P
P	1♦	2♣	Dbl
P	2♥	P	2♠
P	P	P

♣Q	♣3	♣K	♣2
♠8	♠3	♠Q	♠T
♠5	♠J	♠A	♠4
♣A	♣4	♥6	♣6
♣T	♣8	♥T	♦3
♣J	♣9	♥5	♥3
♣7	♠K	♥J	♦T

Both West's, oddly I think, chose to commit their side to 2S on what could easily have been a singleton opposite their K9xxx. I prefer either to pass 2C or make a negative double and pass partner's 2H.

As it happens, 2S is makeable though Ware went down after Nunes found the excellent small trump switch from Ax at trick two. The defence then took the first six tricks. For South's overcall, he could easily have KD and QS instead of AS but whether he would have found the same switch from Qx is open to question of course.

Bach chose to bid 3C over 2S though I prefer pass. With the wide range of hands partner may hold, it's better to let him decide rather than go on just because I have a bit extra. I would expect either 2S or 3C (and possibly both) to usually fail if partner cannot raise my overcall or make a negative double.

4 IMPS to Italy. NZ 34, Italy 16.

Bd: 25

♠

Dlr: N

♥

AQ7

Vul: E/W

♦

J942

♣

J653

♠

542

♠

K86

♥

9654

♥

K1082

♦

AK8

♦

Q1076

♣

A104

♣

♠

Q10973

♥

♦

♣

KQ72

	NT	♠	♥	♦	♣
W	7	5	8	7	5
N	6	7	4	6	8
E	7	5	8	7	5
S	6	7	4	5	8

N	E	S	W
Cornell	Sementa	Bach	Duboin
1♣	P	1♥	P
1NT	P	2♣	P
P	Dbl	2♠	P
P	P

♦A	♦2	♦6	♦3
♦K	♦4	♦7	♦5
♦8	♦9	♦T	♠3
♠7	♠4	♠J	♠K
♦Q	♥3	♥6	♦J
♠6	♠9	♠2	♠A
♣3	♣8	♣Q	♣A
♥4	♥A	♥2	♥J
♣5	♣9	♣K	♣4
♠Q

N	E	S	W
Fantoni	Whibley	Nunes	Ware
1NT!	P	2♥!	P
2♠	P	P	P

♣9	♣Q	♣A	♣5
♣4	♣6	♣8	♣K
♥3	♥4	♥Q	♥K
♦7	♦3	♦K	♦2
♣T	♣J	♠6	♣2
♦6	♦5	♦A	♦4
♥5	♥7	♥2	♥J
♠3	♠2	♠A	♠8
♠J	♠K	♠7	♠4

Another partscore swing. Fantoni/Nunes, playing a weak notrump, declared 2S by North after a transfer sequence. Cornell/Bach, playing a strong notrump, ended in 2S by South. Since East had a doubleton club and a trump entry, the Italians were one down while NZ just made.

4 IMPS to NZ. NZ 38, Italy 16.

Bd: 26

♠

AQJ85

Dlr: E

♥

AQ43

Vul: All

♦

♣

Q73

♠

9762

♠

K103

♥

J109876

♦

A752

♦

♣

AJ105

♣

♠

♥

♦

KQ10863

♣

9862

	NT	♠	♥	♦	♣
W	4	6	6	4	5
N	8	5	6	7	8
E	4	6	6	4	5
S	8	5	6	7	8

N	E	S	W
Cornell	Sementa	Bach	Duboin
	P	3♦	P
3♠	P	3NT	P
P	P

♣J	♣Q	♣K	♣2
♣4	♣8	♣T	♣3
♣A	♣7	♥J	♣6
♠6	♠Q	♠K	♠4
♥T	♥2	♥5	♥Q
♦J	♦4	♦Q	♦A
♠2	♠A	♠3	♦3
♠J	♠T	♦6	♠7
♥3	♥6	♥K

N	E	S	W
Fantoni	Whibley	Nunes	Ware
	2♥	P	P
2♠	P	3♦	P
3NT	P	P	P

♥J	♥2	♥5	♥Q
♦J	♦4	♦K	♦2
♦Q	♦A	♥3	♦9
♣5	♣3	♣K	♣2
♣4	♣6	♣A	♣7
♠7	♠A	♠3	♠4
♥4	♥6	♥K	♦5

Style again helped create a swing as NZ opened with a preempt at both tables.

After opening 3D, Bach ended in 3NT by South and was down fairly quickly after the JC lead and later spade switch established five tricks for the defence. Fantoni declared 3NT by North. He won the heart lead in hand then overtook the JD and continued diamonds, knocking out the ace and happily noting the fall of the 9. Though there are now 9 tricks on top, the blockage in hearts means a spade switch followed by a heart back would beat the contract. Ware instead tried a low club but Fantoni guessed correctly to play low and had no further problems.

4 IMPS to Italy. NZ 38, Italy 28.

Bd: 27

♠

A85

Dlr: S

♥

AQ63

Vul: None

♦

1085

♣

A96

♠

7642

♠

♥

KJ54

♦

AKQ7

♣

KJ1085

♣

Q72

♠

KJ103

♥

1098

♦

J632

♣

	NT	♠	♥	♦	♣
W	7	6	6	6	9
N	6	7	7	7	4
E	7	6	6	6	8
S	6	7	7	6	4

N	E	S	W
Cornell	Sementa	Bach	Duboin
		P	P
1♣	1NT	P	P
P

♥T	♥2	♥A	♥5
♥3	♥K	♥9	♥7
♣7	♣3	♣J	♣6
♣T	♣9	♣2	♣4
♠2	♠5	♠Q	♠K
♥8	♣5	♥6	♥J

N	E	S	W
Fantoni	Whibley	Nunes	Ware
		P	P
1NT!	Dbl	P!	P
P

♦K	♦2	♦4	♦5
♥5	♥8	♥2	♥3
♦3	♦9	♦T	♦Q
♣7	♣3	♣K	♣6
♥7	♥A	♥4	♥9
♦8	♦A	♦6	♠7
♣Q	♣4	♣5	♣9
♣2	♥T	♣J	♣A
♠A	♠9	♠3	♠2
♠5	♠Q

Whibley doubled Fantoni's weak notrump and Ware chose a characteristically aggressive pass, rather than 2C. Double dummy this can be defeated if East leads clubs which declarer must duck twice allowing West two entries to push hearts through. In practice though, it was always going to be a question of overtricks and Fantoni managed eight tricks for +280.

Cornell/Bach play a strong notrump so East overcalled Cornell's 1C with 1NT. He appears to have misread the heart position after the 10H lead but the defence failed to take their tricks so another +90 to Italy and 9 IMPS.

NEW ZEALAND: 38, ITALY: 37.

Bd: 28

♠

Q972

Dlr: W

♥

Q65

Vul: N/S

♦

♣

J6432

♠

AK108653

♥

K10984

♥

J72

♦

A942

♦

♣

Q98

♣

♠

♥

♦

QJ10763

♣

AK107

	NT	♠	♥	♦	♣
W	6	9	9	5	3
N	6	4	4	7	9
E	7	9	9	6	3
S	6	4	4	7	9

N	E	S	W
Cornell	Sementa	Bach	Duboin
			P
P	1♠	2♦	2♥
P	2♠	3♣	P
4♣	P	5♣	P
P	P

♠J	♠Q	♠K	♠4
♥2	♥3	♥K	♥5
♥T	♥6	♥7	♥A
♦T	♦A	♦8	♦5
♥9	♥Q	♥J	♦3
♣2	♣5	♣A	♣8
♦6	♦2	♣3	♦K
♣J	♠3

N	E	S	W
Fantoni	Whibley	Nunes	Ware
			P
P	4♠	P	P
P

♣A	♣8	♣J	♣5
♦Q	♦A	♦8	♦5
♠J	♠2	♠3	♠4
♣9	♣6	♠8	♣T
♠A	♦6	♥4	♠7
♦K	♦3	♦2	♠9
♥5	♥2	♥A	♥8
♥3	♥9	♥Q	♥7

Preempting style again caused a swing here. Whibley opened 4S in third seat on the East cards and Nunes chose to which was correct on this hand as 4S failed by one trick with the bad trump break and QH offside. Meanwhile Sementa was content to open 1S and Cornell/Bach reached an optimistic 5C which had some play single dummy but no chance on the actual hand with Qxx of trumps offside and KH also badly placed. This failed by two tricks for a 6 IMP swing to Italy.

NEW ZEALAND: 38, ITALY: 43.

Bd: 29

♠

AK1064

Dlr: N

♥

AK4

Vul: All

♦

Q102

♣

♠

J975

♠

Q832

♥

J10

♦

AJ73

♦

♣

AJ64

♣

98753

♠

♥

Q876532

♦

K964

♣

Q10

	NT	♠	♥	♦	♣
W	2	4	1	3	6
N	10	7	11	9	5
E	2	5	1	3	7
S	10	7	11	10	5

N	E	S	W
Cornell	Sementa	Bach	Duboin
2NT	P	3♦	P
3♥	P	5♥	P
5♠	P	6♦	Dbl
6♥	P	P	P

♦8	♦4	♦A	♦T
♣A	♣2

N	E	S	W
Fantoni	Whibley	Nunes	Ware
1♠!	P	1NT!	P
2♣!	P	2♦!	P
2♥!	P	3♠!	P
4♣!	P	4♦!	P
4♥	P	4NT!	P
5♠!	P	6♥	P
P	P

♥J	♥2	♥9	♥A
♠4	♠2	♥Q	♠5
♥8	♣4	♥K	♥T
♠A	♠3	♣T	♠7
♠K	♠8	♣Q	♠9
♦2	♦5	♦K	♦A
♦3	♦T	♦8	♦4

A flagrant violation of Burn's law with both tables reaching a slam off two aces. However Italy made the slam and New Zealand did not.

I don't claim to fully understand the Fantoni-Nunes auction but if Nunes intended his 4NT as RKCB, he would have been disappointed to find himself too high after North showed two key cards and the heart queen!

Cornell chose to upgrade his 19 to a 2NT opening and Bach was understandably very interested in slam. I don't know whether they have a way to agree hearts and initiate cue bidding, but once the auction took a quantitative route it was always going to end too high as the hands fit poorly and have considerable wastage.

Obviously a lead of either minor suit defeats the contract. There is some justification for Whibley's trump lead as North will have short trumps plus a ruffing value and East has some useful spade cards that will limit the discards from South on good spades. However declarer will still usually get the ruffs they need and North's fifth spade at least will be established eventually. There's probably not enough of a reason to depart from the usual practice against a slam of making an aggressive lead to try and set up a trick.

Quite a lot of luck was involved in this swing, not only on the lead but also in finding the jack of diamonds and the fact that Fantoni/Nunes were able to declare from North without the benefit of a transfer sequence.

17 IMPs to Italy anyway. NEW ZEALAND: 38, ITALY: 60.

The last three boards were more or less flat with NZ gaining another 2 IMPS and Italy 3 IMPS for extra undertricks. So the final score was New Zealand 40 and Italy 63, or 20-10 in VPs.

EBU Debate Series

2009-07-04T14:46:00.000-07:00

The EBU has published very interesting series of debates on various topics. Each one has two experts presenting opposite arguments on a disputed topic. Here are the links (PDF):

Opening 1NT with a 5 card major
Sponsors playing for national teams
Opening bid with 5-5 in the black suits
Weak NT vs strong NT
Teams vs pairs
Attitude vs count signals
Disciplined vs random preempts
Percentages vs flair
Opening bid with 4-4 in a major and a minor
RKCB vs simple Blackwood
Smith peters

PABF Championships

2009-06-19T16:43:00.001-07:00

I played interclub last night so missed the second half of our Juniors against Australia on Vugraph. Since BBO saves its Vugraph sessions I was able to download it and construct a text file report of the match which is below.

It's incomplete but I think they had some technical problems. The commentary is in a block at the end of each hand rather than mixed in with the play and this means that sometimes the comments refer to the previous hand. I also included a Deep Finesse style double dummy analysis.

Here is the link: PABF_R1-2.txt

UPDATE:
I've added two more, the NZ women against Australia and the open team against Singapore:
Here is the link: PABF_R1-4.txt
Here is the link: PABF_R1-7.txt

The first one is definitely worth a look. I'm not the kind of person who normally knocks women's bridge but there are two hands in there that are really quite special. Board 19 features an eight card spade suit headed by AK that was not bid beyond the two level at one table and not bid at all at the other table. On board 25, Australia came close to making 3NT at both tables.

Responses to 1NT

2009-06-18T01:41:00.000-07:00

One of my pet hates is 'practice Stayman', where a hand with no interest in the majors has to start with Stayman in order to invite 3NT. It helps the defence too much, especially on the opening lead. I'd rather guess between pass and 3NT than do that. There's no need for it because usually the 2S and 2NT bids are assigned meanings that seldom provide any real benefit.

I would suggest the following structure of responses to 1NT:

2C Stayman, always has a major if balanced
2D/H Transfers
2S Range finder or weak with long minor or GF 3 suiter with both minors
2NT Both minors, either weak or GF
3C/D Natural invitational
3H/S Natural slam try 6+ suit

After 2C:
2C-2D-2H: Both majors weak
2C-2D-2S: 5S and 4H game interest but not forcing
2 any - 2NT: invitational
2 any - 3C/D: Natural GF 5+ suit may have no major.
2D-3H/S: strong major 3 suiter, 3H=C shortage, 3S=D shortage
2H/S - jump in a new suit is a splinter.
Other major (i.e. 2C-2H-2S or 2C-2S-3H) is slam try with 4 card support and no shortage).

After 2D/H:
New suit game forcing except 2D-2H-2S which is forcing to 2NT or 3H/S only
Transfer then jump (eg 2D-2H-3S/4C/4D) is a splinter (in support of own suit :). With 6+ major, slam interest and no shortage start with 3H/S over 1NT.
Superaccept in new suit by opener shows values, or 2NT with scattered values but I like to just bid three of responder's suit to avoid telling them anything. May superaccept with a good maximum and only three card support.

After 2S:
Opener bids 2NT with min and 3C with max, then:
3C/D - Signoff
3H/S - Three suiter showing shortage

After 2N:
Opener bids better minor and natural after that. 3H/S by 2NT bidder is a fragment not a real suit as minor three suiters start with 2S.

After 3C/D:
Opener will usually pass or bid 3NT. 3 of a suit implies a fit and willingness to play 4/5 of the minor if stoppers for NT are not there.

After 3H/S:
Cue bidding

I think this handles everything pretty well and is not much to remember. Information about declarer's hand is withheld where reasonably possible. All hand types are covered. One suiters start with transfer if a major or 2C if a minor. Major two suiters start with transfer and bid other suit. Minor two suiters start with 2NT. Major/minor 2 suiters start with transfer if 5 major and 2C if 4 major. Three suiters start with 2C if both majors and 2S with both minors.

If they double our 1NT

Suit bids show a five card or longer suit
Pass forces redouble and bids then show spades and the suit bid
Redouble shows a two suiter without spades. Opener bids best minor then natural.

The advantage of doing it this way is that the hands we are most likely to able to compete on are the ones where we have a 5-4 fit or a 4-4 spade fit. These are identified immediately to allow opener to act if there is further bidding. Despite their double the hand may still belong to us or we could gain from pushing them a level higher.

If they double in 4th seat (ie 1N-P-P-X-P-P) then redouble with one suiter and bid lowest suit with 2 suiter.

Use the same method if they double our 1NT overcall or natural 2NT overcall.

Simulations

2009-06-14T00:40:00.001-07:00

I'm going to start a series of posts simulating outcomes in various bidding situations. I'll try to clearly list the assumptions in each case.

One problem that I can't easily do anything about is the difference between double dummy analysis and results that occur at the table. I'm not sure if any research has been done into quantifying this, but if it has, please let me know.

The big advantage for declarer playing double dummy are that missing cards (e.g. queens) can always be located and singleton kings offside always drop. The bid advantage for defenders are they always find the best opening lead and single dummy defence is just hard because you can't see your side's combined resources in they way that declarer can.

In slam contracts, I think declarer will take more tricks double dummy. This is just because there are fewer decisions for the defence when they hold fewer high cards. Not that defence against slams isn't important, but declarer gets a higher percentage of the tough decisions in slams compared to games and part scores. As a general rule, I'd guess that the higher the contract, the more double dummy analysis inflates the number of tricks taken by declarer. In a contract such as 1NT I expect the defence to do better double dummy than in real life.

If there is a significant difference between tricks taken double dummy and in real life, my conclusions will be wrong by that amount.

Inviting game after single major raise

2009-06-14T00:01:00.000-07:00

This post focuses on the hands that are borderline between passing and making a game try after you open 1H/S and partner raises to 2. I'm making the following assumptions:

1. Partner will have three card support only.
2. Partner's HCP range is about 4-8 (but not 4 HCP if 4333). If you play 2/1 GF then you probably respond 1NT on very weak hands with support so your range is more like 6-9. I'm assuming 2/1 responses can be only around 9+ and will include the hands with three card support and 9 HCP. If not, adjust the strength of the opening hand accordingly.
3. Partner will always decline the game try with 4-5 HCP and always accept with 8. With 6-7 he will choose the correct action 70% of the time (because your game try will enable him to evaluate more accurately).
4. For the IMP calculations, I assume they pass at the other table.
5. I'm also disregarding the possibility that they will balance if you pass. This is obviously quite likely and argues in favour of bidding, not so much to shut them out, but because you no longer have to worry about losing IMPS in the case where the other table just make the two level contract your way.

5431 Hands

	Tricks	7 or less	8	9	10 or more
AK873	HCP=4	2.01%	3.81%	2.78%	1.10%
KJ65	HCP=5	2.88%	6.28%	6.79%	3.20%
AT5	HCP=6	1.33%	5.37%	8.61%	5.98%
4	HCP=7	0.68%	3.72%	10.19%	10.52%
	HCP=8	0.29%	1.77%	7.45%	15.26%

Expected IMP gain from inviting: Vul 0.52, Non Vul -0.08

The numbers in the table are the percentage of hands in each category according to the simulation. Partner's HCP are on the rows and the number of tricks you take on the columns.

So you show a slight loss by bidding on nonvul but it's worth continuing vul. This was a little surprising to me because I would never consider passing that hand, regardless of vulnerability. Possibly I have not increased my standards for making game tries while I have been progressively lowering my standards for single raises. Let's try with a slightly weaker hand:

	Tricks	7 or less	8	9	10 or more
AK873	HCP=4	3.04%	4.03%	1.97%	0.37%
KT65	HCP=5	3.16%	6.95%	5.49%	1.62%
AT5	HCP=6	2.37%	7.35%	8.49%	3.90%
4	HCP=7	0.73%	5.75%	10.66%	7.76%
	HCP=8	0.36%	3.36%	9.77%	12.87%

Expected IMP gain from inviting: Vul -0.66, Non Vul -0.89

So this one is a clear pass. A rule of thumb is that 5431 shapes need a good 15 to invite (or 39 on the 11-7-4-2-1 scale).

6322 Hands

	Tricks	7 or less	8	9	10 or more
AK8732	HCP=4	1.64%	3.60%	3.08%	0.83%
K6	HCP=5	2.50%	7.15%	6.14%	2.20%
AT5	HCP=6	1.42%	6.52%	9.24%	5.38%
43	HCP=7	0.56%	4.78%	9.72%	9.38%
	HCP=8	0.30%	2.63%	9.38%	13.55%

Expected IMP gain from inviting: Vul -0.08, Non Vul -0.5

This one has a good 14 HCP and 37 11-7-4-2-1 points. It's a tossup vulnerable and a pass nonvul.

	Tricks	7 or less	8	9	10 or more
AK8732	HCP=4	1.03%	3.34%	3.64%	1.40%
K6	HCP=5	1.79%	6.04%	7.37%	3.68%
AJ5	HCP=6	0.74%	4.78%	9.36%	7.55%
43	HCP=7	0.33%	3.08%	8.85%	12.04%
	HCP=8	0.12%	1.75%	7.09%	16.01%

Expected IMP gain from inviting: Vul 1.06, Non Vul 0.27

Changing the D10 into a jack makes it worth another move. It's now about an average 15 and has 38 11-7-4-2-1 points.

5332 Hands

	Tricks	7 or less	8	9	10 or more
AK873	HCP=4	3.17%	3.89%	2.44%	0.56%
KT2	HCP=5	3.85%	7.04%	5.38%	1.99%
AQ5	HCP=6	2.58%	7.67%	8.89%	4.28%
43	HCP=7	1.23%	5.06%	9.60%	8.58%
	HCP=8	0.45%	2.81%	8.17%	12.37%

Expected IMP gain from inviting: Vul -0.51, Non Vul -0.77

This above average 16 HCP hand is not worth inviting, though you wouldn't find many players passing it. Let's make it a bit better:

	Tricks	7 or less	8	9	10 or more
AK873	HCP=4	2.38%	4.04%	3.69%	1.26%
KJ2	HCP=5	2.65%	6.40%	7.34%	3.33%
AQ5	HCP=6	1.42%	4.85%	8.51%	6.81%
43	HCP=7	0.66%	3.40%	8.73%	11.36%
	HCP=8	0.31%	2.07%	6.40%	14.39%

Expected IMP gain from inviting: Vul 0.65, Non Vul 0.01

It's now a typical 17 and is worth a move, but nonvul it is still right on the margin. So 5332 hands need quite a lot to invite. There's also less chance they will balance so you may get to play 2S when it makes just eight tricks. However you will also be able to make 3NT sometimes when 4S goes down so a 2NT game try if available could still be worth a shot.

The minimum to invite with 5332 is a very good 16 or 42 on the 11-7-4-2-1 scale.

5422 Hands

	Tricks	7 or less	8	9	10 or more
AK873	HCP=4	1.98%	3.42%	3.77%	0.67%
A2	HCP=5	2.37%	6.09%	8.76%	2.48%
KQT5	HCP=6	1.35%	4.71%	10.66%	5.55%
43	HCP=7	0.81%	3.23%	9.53%	10.61%
	HCP=8	0.31%	1.71%	7.24%	14.73%

Expected IMP gain from inviting: Vul 0.54, Non Vul -0.06

This is a good 16 and has 41 11-7-4-2-1 points. It's just barely worth a move.

6421 Hands

	Tricks	7 or less	8	9	10 or more
AK8732	HCP=4	2.11%	3.67%	3.03%	1.01%
K2	HCP=5	2.71%	6.08%	5.90%	3.34%
QJT5	HCP=6	1.96%	5.73%	7.68%	6.06%
4	HCP=7	1.25%	4.80%	9.17%	9.65%
	HCP=8	0.71%	3.18%	8.34%	13.64%

Expected IMP gain from inviting: Vul 0.06, Non Vul -0.38

This is borderline with 13 HCP and 33 11-7-4-2-1 points.

6331 Hands

	Tricks	7 or less	8	9	10 or more
AK8732	HCP=4	0.96%	4.19%	3.42%	1.44%
A32	HCP=5	1.87%	6.20%	6.77%	3.46%
QJ5	HCP=6	1.05%	5.18%	9.37%	6.40%
4	HCP=7	0.51%	3.68%	9.39%	10.87%
	HCP=8	0.23%	2.12%	7.95%	14.94%

Expected IMP gain from inviting: Vul 0.57, Non Vul -0.06

Here you need 14 HCP or 35 11-7-4-2-1 points.

5521 Hands

	Tricks	7 or less	8	9	10 or more
AK873	HCP=4	1.48%	4.24%	3.87%	0.74%
A2	HCP=5	1.78%	6.24%	6.97%	2.59%
QJT52	HCP=6	1.14%	5.96%	9.53%	5.52%
3	HCP=7	0.41%	3.89%	9.67%	10.59%
	HCP=8	0.22%	2.34%	8.18%	14.64%

Expected IMP gain from inviting: Vul 0.35, Non Vul -0.21

This is right on the margin, again a hand that few players would consider passing. This is possibly the most striking example, partly because people routinely overbid 5-5 hands. It has a good 14 HCP and 36 11-7-4-2-1 points.

Summary

The following is the minimum strength to invite for each hand shape:

Shape	HCP	11-7-4-2-1
6421	13	33
6331	14	35
5521	Good 14	36
6322	Average 15	38
5431	Good 15	39
5422	Good 16	41
5332	Very good 16	42

A further interesting point is how little the vulnerability affects the decision. Even on the marginal hands above, there are only a couple where bidding is right if vulnerable but not if non-vulnerable. Certainly the difference is small, maybe less than a ten. This needs further investigation.

Anti Percentage

2009-06-13T16:32:00.001-07:00

The following hand came up today in the Nickell vs Welland match to decide who plays Fleischer for the second USA spot in the Bermuda Bowl. Others may prefer to write about doubled grand slams making with two top losers, or the correct way to bid a 0607 shape, however the more mundane but higher frequency hands like this one tend to interest me.

How much would you bid with the South hand opposite a weak notrump?

Below is the Meckstroth-Rodwell auction but South at both tables jumped to game after discovering four hearts in the North hand. My instinct was that inviting is enough so I decided to run a simulation. The simulation is based on North as declarer with a balanced 11-14 including 4 hearts. I chose North on the basis that you either play a weak NT or transfer responses to 1C. This probably improves the expected number of tricks a little.

Results are as follows:

HCP	Num Hands	Num Makes	%
11	11120	1696	15.25%
12	9720	2935	30.20%
13	8371	4342	51.87%
14	6784	4495	66.26%

This suggests that inviting is plenty, and opposite an 11-13 hand even pass is possibly correct, especially when you also take into account hands where eight tricks are the limit. Certainly non-vulnerable it is right to pass if partner has a maximum of 13 and just invite if his maximum is 14.

Dealer: N		♠	Q 10 3
Vul: N/S		♥	A 9 8 7
		♦	K 10
		♣	Q 8 7 5
♠	A K 9 5			♠	7 6 4
♥	2			♥	J 10
♦	8 7 6 5 3			♦	Q J 9 4
♣	10 9 6			♣	A K J 3
		♠	J 8 2
		♥	K Q 6 5 4 3
		♦	A 2
		♣	4 2

W	N	E	S

	1♦	P	1♥
P	2♥	P	4♥
P	P	P

11-7-4-2-1 in action

2009-05-31T03:58:00.000-07:00

I was just commenting on the Seniors Camrose on BBO and watched Paul Hackett open 1D (2nd seat, vul vs not) on the hand below:

♠	K Q J 6
♥	7 5 2
♦	K 9 5 4
♣	Q 3

That's 11 HCP on the 4-3-2-1 scale and only 9.6 on the 11-7-4-2-1 scale (7+7+4+4+2=24 * 4/10 = 9.6). That's before adjusting for the doubleton queen. The spades are worth a bit extra due to the honours working together, but still the hand is clearly weaker than an average 10 HCP when evaluated correctly. The Kaplan/Rubens hand evaluator calls it 9.75.

Most players wouldn't open the hand anyway, but I think most would wrongly invite game opposite a weak notrump.

The full deal is below, though it doesn't really prove much as South has a good hand and North's gets better when South bids clubs so the values for game are there. Only the misfit in diamonds and hearts makes it poor.

		♠	K Q J 6
		♥	7 5 2
		♦	K 9 5 4
		♣	Q 3
♠	8 4			♠	10 5 2
♥	K Q J 9			♥	A 6 3
♦	10 8 2			♦	A Q J 7 6
♣	9 5 4 2			♣	10 6
		♠	A 9 7 3
		♥	10 8 4
		♦	3
		♣	A K J 8 7

Weak Notrump vs Strong Notrump

2009-05-30T15:40:00.000-07:00

Below are some arguments that might be made ('weak' is 12-14 and 'strong' is 15-17):

Weak NT

1. When the weak NT is not used, there is an inference that opener is either stronger or more distributional that a minimum balanced hand, so for example, major suit raises by opener don't cover such a wide range.

2. The strong NT leads to more awkward situations where it is necessary to open 1NT offshape, because the hand is too good to rebid 1NT or repeat the suit opened, but is not strong enough to reverse. The weak NT also has some offshape 1NT rebids but they are less frequent.

3. Any 1NT bid leaves your side well placed in competitive auctions because it is limited in both strength and shape, compared to opening 1 of a suit. This favours the weak NT because it occurs more often.

4. Typical methods over 1NT are not well suited to constructive auctions so a weak NT will cause opponents to miss games and/or overbid. Alternatively, they can play overcalls as always sound but risk losing the partscore battle.

Strong NT

1. The weak NT is more likely to go for a large penalty.

2. Playing weak NT, the strong NT hands can be awkward when interference prevents a 1NT rebid. The hand is better than minimum but further action may still be too much.

3. You may lose your own 4-4 major fit after opening 1NT. This is less frequent with a strong NT and also less dangerous because 1NT will often make anyway.

I also think investigating slam or the best game in an uncontested auction is more difficult after 1NT than after 1 of a suit. Traditional methods over 1NT make poor use of the available bidding space. It's not clear which side this favours as the weak NT is more common but the strong NT makes it more likely your side has a game.

I'm not attaching weights to these factors at this stage - just trying to identify the issues.

Four card majors and weak notrump?

2009-05-30T01:06:00.001-07:00

Twenty years ago, four card majors and a 12-14 notrump dominated bridge in the British Commonwealth. If a serious partnership in New Zealand played five card majors and a strong notrump, you'd look at their card and say "Oh yeah, my grandmother used to play that. Do you play Fishbein as well?".

That's not the case any more. In New Zealand and the UK, top pairs are switching to Standard American or 2/1. The Australians have always been a bit closer to the American style, but the weak notrump is losing ground there too. What has changed people's minds?

The obvious reason is that the most successful pairs in World Championships use these methods. But there are some equally obvious objections to this:

If copying World Championship winners is so clearly right, why aren't we all playing Blue Club?
The USA was winning for a long time before we started copying them.
The Americans have markedly superior card play. If Bridge had no bidding and was scored on play alone, I expect the USA would have won even more World Championships.
I'm not entirely sure that the weak notrump has done badly in World Championships, when considered in proportion to the number of players using it.

If we just consider four vs five card majors and 12-14 vs 15-17 NT, I think it's nearly impossible to establish objectively which is best. My gut feeling is about a 60-40 preference for five rather than four card majors and a 75-25 preference for weak rather than strong notrump.

Switching to five card majors may be explained by a desire to use the Law of Total Tricks and Bergen Raises. I think this is an error, for reasons which are spelt out clearly here. However, there's no reason that five card majors and strong notrump need to necessarily go together. If people are switching to a strong notrump for that reason, I'm fairly sure they are just mistaken.

I'll post a detailed explanation of my preference for the weak notrump later.

How much are high cards worth?

2009-05-29T05:18:00.000-07:00

A few weeks ago I built a double dummy solver and have been using it to analyze the relative value of honours. I'm not sure I have the methodology exactly right and will post more on that later, but for now I'll just report the results. This is based on computer simulation of about 130,000 hands.

Card	Average tricks
A	1.2660
K	0.8145
Q	0.4618
J	0.2275
T	0.1133

The trick value is the average extra tricks taken in your side's best fit (or notrump). In order to use this, we really need to convert to a scale with 40 total points in the pack, so that values will be comparable. The following table compares the above simulated results with various point counting methods, all adjusted to the same scale.

Card	Simulated Value	4-3-2-1 Value	6-4-2-1 Value	11-7-4-2-1 Value
A	4.391	4	4.615	4.4
K	2.825	3	3.077	2.8
Q	1.602	2	1.538	1.6
J	0.789	1	0.769	0.8
T	0.393	0	0	0.4

As you can see, the 11-7-4-2-1 count is extremely close to the actual trick taking ability of honours. Probably someone has discovered this before, but I haven't heard about it. Now of course there is a lot more to life than counting points, but I think this can improve bridge decision making. Conveniently, the total of 11+7+4+2+1 is 25 so you can add up your points, double the total twice then divide by ten to get a value corresponding to the 4-3-2-1 scale.

Introduction

2009-05-29T04:45:00.000-07:00

Hi, my name is Nigel Kearney and I live in Wellington, New Zealand. I played international bridge back in the early nineties at Open and Junior level including winning a silver medal in the 1995 World Junior Championships. I've been out of bridge for the last 13 years and am just getting back into it now.

I'm interested in bidding theory and hand valuation so will be posting quite a bit about that.

Welcome to Bridge Thoughts.