Stepping Stone of Thunder

This hand is from the recent European Open Championship pairs championship. The hand needs to be viewed as a 3NT hand by West (sorry about that but the table closed down while I was still analysing it.) The play potentially involves two spectacular plays:

1. Days of Thunder: coined by Eric Rodwell it involves switching to an opponents long suit to hamper communications
2. Stepping-Stone Squeze: first analysed by Terence Reese in his classic "The Expert Game" and involves overcoming a blockage by throwing in a n opponent

North opens diamonds and West has a pretty obvious duck after the A and J - fair play to south if this is from AKJ. Now we see play one. If South can imagine a club blockage then switching to a spade creates a blockage in that suit.

This is not the end of the story if West can put South with 4+ clubs with the AH. He runs six spades and has now played 8 tricks. South must come down to either 4 clubs and the AH or 3 clubs and AQ hearts. In the latter scenario the clubs will run but in the former West can unblock the clubs and exit in hearts - thus using South as a stepping stone to the clubs.

Ricco Van Prooijen's Unusal 5NT

You'll have to go Board 29 (after the jump)

The 5NT bid by Rico Van Prooijen of the Ned Aut team definitely drew a reaction from me as I was watching.

The 1NT bid is one I have come to favour over recent months. A strong NT should be a 6-7 loser hand. It should be your hands in the point range. Here you have a bit too much stuffing and prime cards but then you have no good rebid over 1♠ - except maybe with a nebulous diamond?

Marion Michielson then excellently and fortunately judges her hand worth a quantitative raise. Now there are three conventional ways to respond to this:

1. Plain Vanilla: pass or bid 6NT
2. Ace Ask: pass or show number of Aces (0,1,2..)
3. Baron: bid 4-cd suits upwards

Option number two would probably be the most sensible as with number three you are opening your self to a bad trump split and defensive ruffs. For this reason you would only use three when the bulk of your points are in two suits - which may have the advantage of making partner declarer and protecting their holding in the other suits. For example:

Kx

AKxx

AJxx

Jxx

xx

QTx

KQxx

AKQx

This could produce the reverse auction.

Anyway Marion eventually made the sensible decision that this could not be one or two and thus must be three and helped win her side a deserved 16 imps.

Finding Hand Distributions with Scala

It's a good thing for a language to get out of your way and let you solve problems. It is even better when it helps you solve problems.

I was recently thinking about how many different hand distributions there are in bridge. This can be restated as dividing thirteen elements between four groups. My first thought was that you should make the condition that the any group should receive at least as many cards as the group before it. This meant that if you gave the first group three cards then all the other groups have at least three. With only one card left to distribute it has to go to the fourth group.

I was about to reach for pen and paper when I realized that scala will actually solve this problem for me and I quickly scratched out the following code:

for {

  i <- 0 to 3

  j <- i to (13-i)/3

  k <- j to (13-i-j)/2

} yield (i,j,k,13-i-j-k)

-

So here are your 39 results:

(0,0,0,13), (0,0,1,12), (0,0,2,11), (0,0,3,10), (0,0,4,9), (0,0,5,8),(0,0,6,7), (0,1,1,11), (0,1,2,10), (0,1,3,9), (0,1,4,8), (0,1,5,7), (0,1,6,6), (0,2,2,9), (0,2,3,8), (0,2,4,7), (0,2,5,6), (0,3,3,7), (0,3,4,6), (0,3,5,5), (0,4,4,5), (1,1,1,10), (1,1,2,9), (1,1,3,8), (1,1,4,7), (1,1,5,6), (1,2,2,8), (1,2,3,7), (1,2,4,6), (1,2,5,5), (1,3,3,6), (1,3,4,5), (1,4,4,4), (2,2,2,7), (2,2,3,6), (2,2,4,5), (2,3,3,5), (2,3,4,4), (3,3,3,4)

The distribution ordered by cards in the lowest group is 1, 5,12 and 21. According to the Online Encyclopedia of Integer Sequences this coincides with the rounded partial sum of the atomic weights of the first n elements. It's probably just a coincidence.

Bridge Auction Esoterica

I was surprised to find out that the total number of possible bridge auctions is greater than the total possible number of bridge hands by a factor that is an order of magnitude of 18 - metaphorically this blew my mind.

The total number of bridge auctions is 128,745,650,347,030,683,120,231,926,111,608,371363,122,697,557 - and I had to take a break whilst typing it.

The estimate for grains of sand on earth is 10^20-10^24. Therefore the total number of bridge auctions is likely greater than the square of the number of grains of sands on the planet.

The extra auctions got me thinking that it might be possible to show where every card in the deck is. My first idea was that the cheapest possible bid would deny possession of a card. Start with the two of clubs then the three .... then diamonds, hearts, and spades.* Note that only three actions are needed to determine the location of each card.

* Suit rank goes in aplhabetical order for those unfamiliar with bridge.

The auction would go like this:

Hugh McGann Magic

Hugh Kelsey said in his introduction to "Logical Bridge Play"

the brilliant card player achieves his results through a combination of logic and flair. And although many people may think flair plays a disproportionate part, the expert player, in fact, produces his sometimes unbelievable results almost entirely by the application of logic.

I was reminded of this when I first viewed this hand by another Hugh from the round robin of the World Mind Sport Games - which at first blush I couldn't believe he had found the correct line.



Click the NEXT button in the diagram to follow the play

I will now go through the logic that led to Hugh being the only declarer to make the contract.

Suit Combination: AKQ9 v x(x) and AK9x v Qx

The video below talks about using computers to reduce the amount of calculation in maths. An example of where this is useful would be teaching standard deviation. The formulae are imposing to students and the difference between sample standard deviation and population standard deviation is less important than getting a feel for how standard deviation works.


Still sometimes it is important to understand how the gears work.

I was looking through the Suit Combinations missing 1 point on Bridge Guy's and felt that some of their answers were off so I decided to check them myself.

I ran the first example by hand before turning it over to Richard Pavlicek's Card-Combination Analyzer.

AKQ9 v x : 

BridgeGuys: Finesse the 9 which works 6% of the time.

Drop:

• JTx: 5-3 split is 47.1, 12/112 comb -> 5.05%
• JT: 6-2 split is 17.1, 2/56 comb -> 0.61
• Total: 5.66%

Finesse: theoretically 0%  and JT onside in any combination is obviously 24% ( 1/2*12/25).

• JT onside: 0.3%
• JTx onside: 2.52%
• JTxx onside: 32.7 * 15/70 -> 7.01%
• JTxxx onside: 41.7 * 20/112 -> 8.41%
• JTxxxx onside: 17.1 * 15/56 -> 4.58%
• JTxxxxx onside: 2.9 * 6/16 -> 1.09%
• JTxxxxxx onside: 0.08 but 0% if AKQ9 in dummy
• Total: 23.99%

Fascinating Mini-Tournament

I played a tournament on BBO the other night that, despite only lasting six hands, brought up some interesting hands.

On Board 1 our opponents bid to a cold 5♦ that left us looking to hold it to 11 trick to break even.

For the five diamond bid I expected dummy to hit with values in clubs (otherwise bid a major or look for 3NT). I led off with a low ♣ running the risk of losing tricks in the majors. However, this is matchpoints and if I picked the wrong major it could be just as bad. I led low to give the impression of an honour but, unfortunately, declarer had no decision to make.  Declarer ruffed a heart to lead a trump and partner took their A♦. If they had ducked this, another trump lead would have given them an opportunity for the Days-Of-Thunder play: leading back a club to prematurely cut declarer off from dummy.

On board two partner opened 2NT on an 18-count and went down 3 vulnerable.

Another Everything-Is-Okay Block (This Is Not A Repeat)

The following hand is from the Terence Reese book 'The Most Puzzling Situations in Bridge'. We should all be familiar with the technique by now - from here and two more here.





West leads the K♥ against your 6♦. You have 11 tricks if the spades are breaking and a heart ruff will see you home. What if the spades are not breaking? Then you will have to bank on the ruffing finesse in clubs. To keep yor options open, draw trumps and play K♠ then A♠. You have 4♠+1♥+5♦+1♣ + 1 ruff = 12 tricks.

Another Everything-Is-Okay Block

The following hand is from the Terence Reese book 'The Most Puzzling Situations in Bridge'.

West leads the K♦ against your 6NT. You have 11 tricks if the spades are breaking with an easily established twelfth in diamonds. How do you play?

Playing Them The Wrong Way Round

Many people are familiar with the tactic of running a long suit to keep control. In my salad days I would have ducked a trump in the following hand. That is fine for teams but now I play a lot more matchpoints.After West leads the AKJ♥, the correct technique is to cash two trumps in the long-trump hand and run the diamonds when the suit does not break. I like to call this play the Everything-Is-Okay Block because I can afford to block this suit if everything is okay.

Speed Of Lightning Play

Another hand from the Junior Invitational in Beijing. I have often wondered whether I was lucky or good on this hand - not that there is anything wrong with that. I received a diamond lead and, through some rather specious reasoning, decided I would prefer to lose a trick to East. I won the A♦ and led the T♣ from hand. This hit the jackpot when West ducked from ♣Qxx.

I am currently dipping in and out of 'The Rodwell Files'.In the section 'Speed Of Lightning Play', I came across the hand below. East was Fredin from Sweden. When he received the T♥ lead, he reasoned that South probably had awkward holdings in the minors. After the Q♥ won, he came to hand with a diamond and led a low club. South ducked and the hand is routine from there. This is a Speed Of Lightning Play, taking advantage of positions where defenders play low quickly to avoid giving away their holdings in a suit.

After seeing the latter hand, I think maybe I made the correct play on the former hand - albeit for the wrong reasons. Do you think I was lucky or good?

Shortshake: Transferring The Ruff

Another play named by Eric Rodwell in the 'The Rodwell Files' and the example is from the Imagination and Technique in Bridge" by Tim Bourke and Martin Hoffman.

West leads the K♠ and East follows with the 2♠ You win the trick and cash the K♦. How do you continue? You have ten tricks with 6♦+2♥+A♠+A♣. If hearts are no worse than 4-2 then you have the entries to establish the hearts. How do you cope with 5-1 hearts?

Good Defence From Singapore

b
This defence was easier to find than I first thought. East's 2♣ bid was probably a general game force. West can place him with at most the KQJ♣, QJ♦, and the J♠ outside of hearts. Therefore he must have the A♥ for the 2♣ bid. He still had to find the trumpp switch.

Note if East led the A♥ instead, he must find the diamond switch. Now when south ruffs and leads a spade, West can jump in with the Q♠ to lead another diamond. Dummy only has the K♥ left and thus the Q♥ will be promoted to the setting trick.

This may seem like a very kind hand to display but I have a hand for next week where I called the director on my own partner. He was from the Malay Peninsula and I did not want people thinking I had a bias against that particular area.

Expert Shortcake

The shortshake is a play named by Eric Rodwell in the 'The Rodwell Files' and both these examples come from 'The Expert Game' by Terence Reese.

On the first hand South plays in 6♣ after East has made a pre-emptive overcall in spades - probably no Michael's* in those days. West leads the A♠ and continues with a spade. South discarded a diamond and East showed out on the Q&clubs. South turned to diamonds, playing the AK and ruffing the third round. Now they tried to get back to hand by playing A♥ and ruffing - but West over-ruffed.

To avoid this, at trick two, South must discard a low heart on the K♠.

* I am going with the apostrophe against the spelling from all the resources - et tu Wikipedia?

More Shortshake, LOL

Another play named by Eric Rodwell in the 'The Rodwell Files' and the example is from the books of Terence Reese.

West leads the Q♦. You play low to presere the K♦ as an entry (and in case East is void). East follows to the diamond but discards on the first round of trumps. You have 11 top tricks but the bad trump break means you will need to develop a trick in either spades or diamonds.

More Shortshake

The shortshake is a play named by Eric Rodwell in the 'The Rodwell Files' and the example from the books of Terence Reese.

West leads the J♠. One trick must be loss to the A♣ and possibly one to the K♦. It looks as though only a ruff threatens the contract. How would you play?

Hands From Ireland-Scotland Camrose Match

The following are some hands from Sunday's Camrose match between Ireland and England: Analysis from the Scotland-England match is available here.

Robson Gaffe:




Just to show that even the best can make the easiest of mistakes. South ducks the spade lead and wins the second round. For his vulnerable 2♠ opening with ♠Q96543, West must have the A♦. Therefore you would think that there is very little to the play. Robson must have seen something else. After one round of clubs he cashed the AQ♥ - blocking the suit! After this there was no recourse.

Hands Of Note From The Scotland-England Camrose Match

The following are some hands from Saturday's Camrose match between Scotland and England:

Costly Non-Costly Lead:



Forrester played in 3NT and North led his fourth highest diamond. Leading the beer card instead of the J♦ has no effect on the play except to complicate defence. South did well to apply the Rule of 11 and played low. Forrester won the A♦ and cashed the AK♣. When he found the bad break he led a low diamond. North did not read his partner's duck and inserted the T♦. Forrester played low from dummy and the defence's goose was cooked. South switched to a heart, won by North who continued with two more rounds, the final one into declarer's AT♥. The fourth round of hearts squeezed North for an overtrick.

Shortshake

Another play named by Eric Rodwell in the 'The Rodwell Files'. The play involves the discard of a non-loser to enable an earlier ruff in the discarded suit. I have located a few more ex libris Terence Reese. I will do one hand per post.

In 4♥ you receive the T♦ lead. If this is a singleton you are probably dead in the water. Can you do anything if it is a doubleton?

My Favourite Hand

The above hand occurred in the Junior Individual in Beijing 2008. I opened three diamonds first in hand and this was passed around. West opened a top spade and, not wanting to set up dummy's Q whilst dummy had an entry, switched to the the Q♥ - after a lot of thought.

You are on the dummy, how would you continue?