[Roger_L]

A few weeks ago I was leader in a 4♥♥-contract. After the dummy came on the table I counted 4 losers.

Dummy and my hand were holding 10 trumps together. The missing cards were King-x-x.

My LHO started with ♠A. In dummy ♠xxx. In my hand ♠Qxx. LHO followed by a small ♠. My RHO cashed the king and returned another spade, trumped by LHO.
I won the next trick in my hand and played a small ♥. On the table you see ♥AQJx. LHO followed by a small ♥. What now ? Who has the ♥ king ?
I played the ace because the possibility of a 2-1 holding by the opponents is 78%. A 3-0 holding only 22%. And… my LHO was holding Kxx. Result: 1 down.

One of the best players of our club told my he ALWAYS take the finesse.
For me it’s difficult to believe I did wrong using the probabilities.

Who can give information ?
Thx

[manudude03]

If you use vacant spaces, RHO has shown 5 cards (5 spades) and LHO 4(2 spades and 2 trumps- the low ones being forced). That leaves 9 spaces left for LHO and 8 for RHO, so LHO is a slight favourite to hold the ♥K

[mgoetze]

Let's ignore the additional information from the spade suit for now. A priori, the following trump holdings are possible:

A) Kxx void 11%
B) Kx x 26%
C) xx K 13%
D) x Kx 26%
E) K xx 13%
F) void Kxx 11%

LHO has shown up with 2 small cards so you are down to A or C. Indeed this would suggest playing the Ace is correct. However, given that LHO started with 2 spades and RHO started with 5 spades, the probabilities change to 15.14% for C and 17.03% for A, therefore the finesse is slightly better.

You can get these probabilities by using Richard Pavlicek's calculator:
http://www.rpbridge....cgi-bin/xsb2.pl

Give 11 and 8 vacant spaces and calculate the splits for 3 cards.

[the hog]

Forget the percentages arguments; these players are bean counters. Consider the lead; the lead from Ax is a pretty desperate lead, UNLESS you have a trump trick and hope to put partner in. Hence hook.

[whereagles]

Why is Ax a desperate lead? I would have thought so 3 years ago, but changed my mind since I read Bird/Anthias and now rate the lead as "normal".

[ArtK78]

I would consider it to be an agressive lead, but not a desperation lead.

Furthermore, we were not provided with the auction. Perhaps a spade lead stands out.

[Roger_L]

to all: thx for the answers

[mikeh]

the hog, on 2014-December-10, 06:39, said:

Forget the percentages arguments; these players are bean counters. Consider the lead; the lead from Ax is a pretty desperate lead, UNLESS you have a trump trick and hope to put partner in. Hence hook.

This is silly.

The correct approach is more subtle, and requires (at the least) knowledge of the auction.

As Reese once wrote/said: there is no such thing as a blind opening lead, only a deaf opening leader (before bidding boxes or the internet, lol)

Thus one cannot draw inferences from an opening lead absent the auction and both dummy and declarer's holdings.

In addition, in some games, the lead of A from Ax is seen as 'standard'. It was definitely a common lead in my circles when I was a beginner, and I still see a lot of inexperienced players do it. So one needs to know something about the level of skill of our opps as well.

In the absence of such information, the bean counters rule, as they should.

Btw, these issues render the 'good player at the club' advice little better than yours. No good player would 'always' take the finesse, but maybe the quote was inexact or maybe the player didn't want to qualify the advice by noting that in reality this decision always depends on context. I think the correct advice would be: given what you have told us, and lacking any other information (which we would have at the table) then I would always finesse.