Passing up some +EV plays is correct

Take the following situation...

$20+2 Party SNG

Blinds 150/300

BB has 4000 chips
UTG has 300 chips (Will be all in next hand)
SB has 2000 chips
HERO is SB and has 1700 chips

Preflop you are dealt A10os. UTG folds. SB shows his cards face up (KsQs) and shoves all in. Easy fold?

The call is +EV for that specific hand (slight favorite) and therefore would be an autocall in a cash game. But in a tournament things change.

You will get at LEAST 3rd place 75% of the time assuming you do nothing and SB is forced into 2 coinflip situations.

I am no math expert by any means, but I will take a stab at it here. By calling all of you chips in with a slight favorite (55/45).

There are two outcomes to the allin:

1) You win and double up, criple the other player, and should be able to coast into at least 2nd most of the time.
2) You lose out of the tournament and get nothing.

Situation 1:
If you do double up (55% of the time) you will have about even chips with the other player at heads up, thus you will get first place 27.5% of the time and second 27.5% of the time.

Situation 2:
You get 4th 45% of the time.

100%
27.5% +4buyins +1.1
27.5% +2buyins +0.55
45% -1buyin -0.45

+1.2

Therefore the EV of calling is about 1.2 buyins.

And folding? Whats is the EV of that?

If you fold, there are two outcomes:

1) You fold and 75% of the time you get at least 3rd.
2) You fold and 25% of the time its a coinflip for 4th or 3rd.

75% You make it ITM and chips are ~ 2000 (you) 2000 4000.
I will assume the following:
When you get ITM you will get in third 50% of the time, second 25% of the time and first 25% of the time with these stacks.

First 18.75% +4 buyins +0.75
Second 18.75% +2 buyins +0.375
Third 50% +1 buyin +0.5
Fourth 12.5% -1 buyin -.25

+1.375 buyins

Soooo..

EV of calling - EV of folding
1.2 - 1.375
-0.175 buyin EV by calling vs folding.

Calling is incorrect.

Of course, this is VERY close, and perhaps I am assuming too much. Obviously this is a very simple example, but you get the idea, it can apply to alot of situations you face late game in a SNG.


The whole point of this post is to show those of you who think that +EV moves are always correct (hand specific) that it may sometimes be incorrect to CALL A push late in a tournament with only a slight edge. Many good players already know this, but it was something I had to struggle with alot when I first started and this post might somehow help someone.

Of course if you were the one RAISING and you got CALLED by someone else holding KQs, then so be it. Calling with a slight edge is different entirely.

Cheers