All bridge in one hand

[Fluffy]

Federico Goded wrote a famous article in 1999 called All Bridge in One Hand, where one simple hand with a simple problem morphed slowly from beginner level towards world class in 10 steps.

 

Now he has expanded the series from 10 to 40 hands. And you can play find all the hands on my website, look for them on the Courses section, or just click here: http://www.bridgegod.com/showset.php?setid=7

 

The difficulty is normally increasing, so if you are good you might want to start from the middle or better.

[Lord Molyb]

Checking it out now, I will edit in what I think later.

Deal #

18

was easier than I expected.

Edited February 22, 2014 by Lord Molyb

[Jinksy]

I'm getting frequent (though not reliable) error messages when I try and load a new hand.

[1eyedjack]

NIcely done, sir. Wish I could give more than one up-vote. Minor point re the page design: It took me a while to find the vertical scroll bar to get to hands 5+. Very thin strip with same background colour. (Opera)

[Jinksy]

Is there any commentary? On some of these the NS hands look identical, so I'm not really sure why I'm supposed to follow different lines between one and the next.

[karlson]

I enjoyed these. Shades of bridgemaster.

[Lord Molyb]

#

26

was really easy too.

 

First one I actually got wrong was #35, played for the wrong squeeze. Then #36 stumped me, a lot harder than I thought.

[Fluffy]

Is there any commentary? On some of these the NS hands look identical, so I'm not really sure why I'm supposed to follow different lines between one and the next.

 

You are suposed to find a single line that makes on all lie outs (or switch when you see some break or the like), look at how FGoded plays the boards for more info.

[Fluffy]

Checking it out now, I will edit in what I think later.

Deal #

18

was easier than I expected.

 

Just out of curiosity, do you remember if you cashed ♦A before winning ♦K in dummy?, I had some discussion with my father about his percentages, he claimed that you should test for ♦Jx before cashing dummy's third club winner, but my calculations said that inmediate loss from ♦5-1 was too dangerous. There was another hand with same NS cards but different lie out where LHO had Jx and ♣xx. I ended up changing that one board.

[Lord Molyb]

Just out of curiosity, do you remember if you cashed ♦A before winning ♦K in dummy?, I had some discussion with my father about his percentages, he claimed that you should test for ♦Jx before cashing dummy's third club winner, but my calculations said that inmediate loss from ♦5-1 was too dangerous. There was another hand with same NS cards but different lie out where LHO had Jx and ♣xx. I ended up changing that one board.

No, I played the king first.

[Jinksy]

You are suposed to find a single line that makes on all lie outs (or switch when you see some break or the like), look at how FGoded plays the boards for more info.

 

But as far as I can see eg Bs 4 and 5 have identical N/S cards. Why does the solution differ?

[Lord Molyb]

But as far as I can see eg Bs 4 and 5 have identical N/S cards. Why does the solution differ?

The point is to find a solution that makes against both distributions.

[kgr]

Thanks, this was fun.

Some comments:

- I think it would be better to show all cards immediately after the claim and before hiding them by show results.

- Is there an undo (fi after misclick)?

- I didn't find how to show the play of FGoded

Just out of curiosity, do you remember if you cashed ♦A before winning ♦K in dummy?, I had some discussion with my father about his percentages, he claimed that you should test for ♦Jx before cashing dummy's third club winner, but my calculations said that inmediate loss from ♦5-1 was too dangerous. There was another hand with same NS cards but different lie out where LHO had Jx and ♣xx. I ended up changing that one board.

Playing ♦A looses if:

♦x: 12.12%

and wins if both:

♦Jx : 16.14%

♣xx: 15.4%

Maybe this is not complete (and how do I calculate total %?), but it feels that it is better not to cash ♦A

[gszes]

I started at the beginning and while this is a nice series at the

the beginning (making sure you heave the trump 7 in hand for repeated

trump finesses :)) by hand 22 (where I stopped) the final contract was

so ridiculous the umm err "world class" players expected to make the

contract needed some advanced bidding lessons on how to stay out of

such ridiculous contracts. I am sure it does nothing but get worse

and worse and worse. Good exercise for imagination maybe but by board 22

it was already in the trivial pursuit realm.

 

I found the programming features well done though keep up the good work:)

 

As an aside--I noted some people said they could claim---I could not find

this feature anywhere and robotically playing the final 4 to 7 tricks was kind

of irritating (ok at first but after 10 15 20 hands sheeshhhhhhhhhhhhhhh

[1eyedjack]

I think that there is a bug in hand 33. You can make it by playing like a complete moron:

 

 

Ruff trick 2 with ♠10

Unblock ♣AK

Hook ♦J

ruff ♣ with ♠J

Cross to ♦K

Ruff ♥8 low

And now it gets surreal:

Cash ♦A, and East discards ♥ when he could ruff for setting trick

Ruff ♦, and East again discards instead of overruffing with ♠K

Run ♠9

And now you are left with ♠AQ sitting over ♠Kx.

 

 

 

 

[1eyedjack]

I think that there is a bug in hand 39. Not quite so moronic a play but it works:

 

 

Ruff trick 2 with ♠9

Overtake ♣K with ♣A

Run ♠8

Repeat ♠ finesse - bad news.

Now try to cash ♦AKQ hoping for RHO to follow throughout.

He doesn't follow to third ♦, but neither does he ruff.

Now you can make via ♣ finesse, ruff ♥, cross back to ♣A and uppercut.

 

 

[1eyedjack]

by hand 22 (where I stopped) the final contract was

so ridiculous the umm err "world class" players expected to make the

contract needed some advanced bidding lessons on how to stay out of

such ridiculous contracts.

 

If it helps, perhaps picture it as Matchpoints and you are in 4S trying to make 6 for a higher percentage?

[1eyedjack]

Perhaps it detracts slightly from the elegance of the hands that in some cases they rely on misdefences.

Hand 40, for example, is beaten by a Club lead at trick one. But that is churlish. The actual lead is perfectly normal.

Perhaps less forgivable is hand 39, where either minor switch at trick 2 beats it.

 

 

[Fluffy]

Thanks, that is a big bug you detected. I instructed defender to not ruff so that if you don't tap yourself you end up endplayed in your hand. Obviously this is moronic if he is 4th in hand. Gonna change it now.

 

For the claim button to appear you need to hide the a trick when all outstanding trumps are out and you have enough top winners. To hide a trick you need to click anywher on the screen after it has finished except a playable card for next trick.

 

 

Same happens for showing full hand, just click anywhere at the end and it will show up.

 

EDIT: Fixed now, hope I Didn't break something on the proccess :)

[cherdano]

For the claim button to appear you need to hide the a trick when all outstanding trumps are out and you have enough top winners. To hide a trick you need to click anywher on the screen after it has finished except a playable card for next trick.

That's very counter-intuitive, it would be good to fix that.

 

Also, while it's a great site - I hope you don't mind an honest opinion: I really don't like the colours. Maybe that's the kind of thing where an new person who hasn't been involved in the site development so far can give useful input.

[Fluffy]

Thanks Arend, I am convinced now that I need to remake how things look like, a friend made a suggestion with mostly green as background and I will do it if I ever feel like it. Do you have any other suggestion?

 

I am stilll thinking about board 17, that was the only hand I made, I included it yesterday when I found my father's math was wrong (see kgr's explanation)

[cherdano]

Board 25:

 

 

Alternative line: Play for Kx onside.

 

I think this is _extremely_ close. Kx and Kxx are almost equally likely (depends a bit on whether we are supposed to infer s.t.h about the heart length), so it roughly depends on whether playing for the (squeeze or ♣T dropping) is over 50%.

 

Below is an output from Pavlicek's Dual suit break analyzer. I excluded voids (partly to save some work, partly because no lightner double), and didn't specify vacant spaces for simplicity (should do that once for Kx and once for Kxx obviously). In the "Plan A" column, I entered the number of combinations for which the squeeze would work for the given distribution.

 

According to this calculation (which is obviously a bit imprecise), the squeeze works 48% of the time.

 

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

Dual Suit Break Analysis

Suit 1 missing: 6

Suit 2 missing: 7

West vacant spaces: 13

East vacant spaces: 13

Known: E1>0 and E2>0 and W1>0 and W2>0

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

Case Wgt W1 E1 W2 E2 Ways Pct PlanA Pct

1 100 5 1 6 1 6x7 0.03 42 0.03

2 100 5 1 5 2 6x21 0.35 126 0.35

3 100 5 1 4 3 6x35 1.47 210 1.47

4 100 5 1 3 4 6x35 2.65 90- 1.14

5 100 5 1 2 5 6x21 2.12 36- 0.61

6 100 5 1 1 6 6x7 0.71 6- 0.10

7 100 4 2 6 1 15x7 0.29 105 0.29

8 100 4 2 5 2 15x21 2.21 315 2.21

9 100 4 2 4 3 15x35 6.63 525 6.63

10 100 4 2 3 4 15x35 8.84 225- 3.79

11 100 4 2 2 5 15x21 5.30 90- 1.51

12 100 4 2 1 6 15x7 1.33 15- 0.19

13 100 3 3 6 1 20x7 0.98 20- 0.14

14 100 3 3 5 2 20x21 5.30 60- 0.76

15 100 3 3 4 3 20x35 11.78 300- 5.05

16 100 3 3 3 4 20x35 11.78 300- 5.05

17 100 3 3 2 5 20x21 5.30 60- 0.76

18 100 3 3 1 6 20x7 0.98 20- 0.14

19 100 2 4 6 1 15x7 1.33 15- 0.19

20 100 2 4 5 2 15x21 5.30 60- 1.01

21 100 2 4 4 3 15x35 8.84 225- 3.79

22 100 2 4 3 4 15x35 6.63 525 6.63

23 100 2 4 2 5 15x21 2.21 315 2.21

24 100 2 4 1 6 15x7 0.29 105 0.29

25 100 1 5 6 1 6x7 0.71 6- 0.10

26 100 1 5 5 2 6x21 2.12 36- 0.61

27 100 1 5 4 3 6x35 2.65 90- 1.14

28 100 1 5 3 4 6x35 1.47 210 1.47

29 100 1 5 2 5 6x21 0.35 126 0.35

30 100 1 5 1 6 6x7 0.03 42 0.03

Totals 90 90 105 105 7812 100.00 4300 48.04

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

 

 

 

[Fluffy]

So I should add ♦10 to the equation to make the squeeze better

[Lovera]

#

26

was really easy too.

 

First one I actually got wrong was #35, played for the wrong squeeze. Then #36 stumped me, a lot harder than I thought.

A double squeeze that i have played like hibryde retaining comucating in clubs too instead of twin entry lonely in diamonds (ruffing a club)(Lovera)