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A bridge problem-corner conducted by Richard Cowan rcowan@mail.usyd.edu.au Originally this column was
written for the Bulletin
of The
Lindfield Bridge Club The bridge problems in the Chances column involve an assessment of probabilities for competing strategies. Brief solutions are reported in the Bulletin, while full solutions appear on this website. Columns 1-9 were run as a Club competition. From Column 10 onward, the competition format was dropped and the Chances column merely discussed bidding and card-play issues where probabilistic analysis is fruitful. |
The most-recent CHANCES columns (problems 10-18)
The CHANCES competition archive (problems 1-9)
Links to correspondents: Luigi Salemi's analyser, Marco Troiani's Infobridge site
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Chien-Hwa Wang, on pp38-9
of his book "The
Squeeze at Bridge",
discusses this end position. South is on lead in a NT contract and needs
the remaining three tricks. There are four spades outstanding, including
the
What is the chance that
South will make the contract from this position, using his best line
(which begins with play of the
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North |
A solution is available; see the Column 18 download . It is a pretty simple problem.
Column 17.
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North-South bid to 7NT with
the cards shown in diagram (a), using an auction which marks South with a
3334 shape and 17-18 HCP (including one ace and two kings). West leads the
What is the chance, given
the information to date, of making 7NT from situation (b) using the best
line (which obviously starts by cashing the
You'll have to consider
all possible discards for the opponents. As an example, what is your best
line and chance of success once (c) is reached if both discard a diamond
on trick 11 and West plays
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a) 7NT North |
b) end-game North |
c) trick 12 North |
A solution is available; see the
Column 17 download -- which has some interesting theory
about "vacancies", "free choice issues" and "game theory"
Column 16 (from the club's "Feb-March, 2006" Bulletin).
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Deal (a) occurred during the 2005 Bermuda Bowl. The Australian Open team was playing Brazil. The contract at both tables was 7H. In attempting to understand better the issues entailed in such a hand, I posed a somewhat simplified version, deal (b). My “generic” form of the deal has solid trumps (having no risk of over-ruff) and no lower honours nor high pips in the side-suits. So your resources are limited to the 9 trumps, the 5 outside high tricks and potential long tricks in the minor suits.
Suppose,
on deal (b), that West
leads
the
Thanks to Len Dixon for drawing my attention to the deal. |
a) actual North |
b) simplified North |
For the chances of success with deal (b), and some remarks
on what actually happened
in the Brazil-Australia match with deal (a), see the Column 16 download.
Column 15 (from the club's "Oct-Nov, 2004" Bulletin).
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What is the chance of
making 7H
by South on deal (a)? You have 11 high tricks and the potential to ruff
two spades. My guess is that you will rate your chances highly on this
"no-loser contract".
What about deal (b) played in
6H
with the
Deal (e) no longer has
the
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a) 7H North |
b) 6H North |
c) 7H North |
d) 6H North |
e) 6H North |
f) 6H North |
For answers, see the Column 15 download. The column provides some theoretical insights into 5-4 fits.
Column 14 (from the club's "Jan-Feb, 2004" Bulletin).
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After the auction
1D-1H <> 2NT-3NT, South
received the
There
appear to be two distinct lines of play. One of these, Line A, is the play
of the diamond suit, hoping to derive 4 tricks from the suit. The other
line, Line B, tackles the heart suit first – low toward
How should one play the hand? Thanks to Les Varadi for providing the deal. |
North |
For the solution, see the Column 14 download.
Column 13 (from the club's "Nov-Dec, 2003" Bulletin).
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You pick up a balanced hand of 16 HCP and plan to open a 15-17 1NT. Partner, however, opens before you, with 1NT. I saw such a hand recently; the responder bid 6NT directly. Was it wise, do you think, for him to bypass the ace-asking convention? What do you think the chances of the partnership missing two aces would be -- given responder's 16 HCP and the information that opener's range is 15-17? |
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For an answer which has some interesting
tables about the
likely holdings of control cards when the partnership
has a given number of HCP, see the Column 13
download.
Column 12 (from the club's "Aug-Sept, 2003" Bulletin).
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As dealer sitting South, in a tournament with IMPs scoring, you open 1S showing 5+ spades. LHO passes, partner bids 1NT (the usual 6-9 with at most 2 spades) and RHO passes. What do you bid? 2H or Pass? EW are vulnerable. Take a view before reading the analysis. |
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For answers, see the Column 12 download.
Column 11 (from the club's "June-July, 2003" Bulletin).
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All of the CHANCES columns to date have focussed on problems of card play. Yet considerations of the probabilities also arise in bidding; a recent hand from Thursday-night bridge at Lindfield illustrates this. As South you must decide where to place the contract. Your partner has shown 25+ HCP, with no 5-card suit and no singleton. Upon enquiry you learn that he has 3 aces and 3 kings. Do you bid 7NT or subside in 6NT? |
North |
For answers, see the Column 11 pdf download.
Column 10 (from the club's "April-May, 2003" Bulletin).
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On each of these deals, the
bidding proceeds
1D-1H<>2H-4H.
On (a), a trump is led to East's K. He leads a trump back to West's A and a 3rd round of trumps is led. How to proceed? On (b), West leads the
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(a) North |
(b) North |
For answers, see the Column 10 pdf file. There is a common theme and some very useful theory!