Do you call 13 outs on the flop when he has an overpair?

Sorry fatguy, I disagree with what you said because in the question he said he had 13 outs, and I'm not saying you did your calculations wrong, but it's really easy to find out if this is a good situation to get it in or not. We're calling 100 to win 160, or 1 to 1.6. If know for sure we have 13 outs, and it's on the flop(kidsoldja, I don't think you realized that you have 2 chances to hit it) then I think I remember reading somewhere that you calculate how often you don't hit it and subtract it from one. If we know 7 cards, there are 45 left, so that leaves 32 bad cards (32/45). On the turn(we didn't hit) we know 8 cards, there are 44 left, so that leaves 31 bad cards (31/45). 1- (32/45X31/45) = 1-0.4898765%, we'll hit 51% of the time. Snap call in this spot, from a glance (13X2=26) we know we'll hit about 1 in 2 times, so pretty much any pot odds tell us to call in the heat of the moment. You should always call here with so many outs, unless you're deepstacked in the main event and phil ivey and you take the nitty route because you don't want to take risks and can read peoples souls and win chips without winning hands

Hm, I've come up with slightly different calculations than both of fatguy and newfish; here's how I see it:

Assume we hold T, 9 versus villain's K,K

Flop is
9, 8, 7

We have 13 outs:
Two 9s
Four 6s
Four Js
Three Ts
= 13

Here's the stove:

Code:

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 990  games     0.001 secs   990,000  games/sec

Board: 9d 8h 7s
Dead:  

                equity         win           tie        pots won    pots tied    
Hand 0:     54.141%      52.93%     01.21%      524       12.00   { KhKs }
Hand 1:     45.859%      44.65%     01.21%      442       12.00   { Td9h }


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So we have 45.859% equity versus the overpair. Basically, we can call for our stack depending solely on whether the amount of dead money in the pot overtakes the importance of our disadvantage in equity.


Example 1: Hero and Villain's stacks are 100$ each; 15$ already in pot

Villain is all-in for 100$; we must pay 100$ to win 115$; this implies we need 46.5% equity, which we do not have; so we fold.


Example 2: Stacks are same as in (1) except there is now 40$ already in the pot

Villain is all-in for 100$; we must pay 100$ to win 140$; we now require 41.67% equity, which we have; thus we call.

Yeah I should point out that the way I've constructed the above hand leaves open the possibility for ties and redraws, which is probably the only distinction between my calculation and newfish's "pure 13 outs" numbers.

i.e. KK has redraws against our two-pair or set draws; he will make a better hand by drawing a K on the river even if we bink one of these 5 outs some small % of the time.