AK975 \ J86 - 5 tricks required

[guidopc]

I am interested in the math behind the title figure.

In particular if it's correct to finesse the Q after the 10 drops right in the first round.

And how this could change after some defender card can be counted out.

Anyone has done this analysis already or is able to suggest a link\book?

Thank you

[Stephen Tu]

It's better to play for the drop. Because individual 3-2 breaks are more common than individual 4-1 breaks. In general with suit combinations, individual more even breaks are more common than more extreme splits. 3-2 > 4-1. Individual 2-2 break > individual 3-1. (But collectively there are 4 3-1 breaks and 4 1-3 breaks and total up to more than the 6 2-2 breaks).

 

If you bias the deal it becomes tossup if the T dropper has 2 fewer vacant spots, so more (e.g. preempt, he has 6 in another suit and his partner has 3) then finesse becomes better.

 

Books:

Roudinesco dictionary on suit combinations

Programs:

suitplay - http://www.suitplay.com

Pavlicek card combination analyzer

http://www.rpbridge.net/cgi-bin/xcc1.pl

[WesleyC]

I find this Suit Combination Calculator to be the most user friendly resource.

 

In the missing cards box, you should input QTxxx (because the X's are equivalent) and click calculate.

 

The apriori odds of Qxxx - T at 2.8% and xxx - QT at 3.4%.

 

However, as Stephen points out this could easily change with additional information.

 

If a side suit was known to break 3-6, you would adjust the vacant spaces in the top right to "10" , "7".

 

In this new situation, Qxxx - T is 4.8% and xxx - QT is 4.1%.

[Mbodell]

You also need to think what if the opponent plays the T from Tx. On some holdings you have to worry what if holding the QT they play the Q too.

 

Note there are other lines too like the double finesse line that also picks up stiff T off.