This is complete nonsense. When the player shoves, before the cards are revealed, you rate him more likely to be strong. Every 6 actions we see, on average, are 3 strong player shoves, 1 weak player shove, and 2 weak player folds. Given a shove, he's a 3:1 favorite to be a strong player. Once he reveals AK (or a top 33% hand), it's back to even money. Every 6 actions will consist of 1 strong top 33% shove, 1 weak top 33% shove, and 4 outcomes where there's no shove or no top 33% hand. That's 50/50, just like you started with. It's Bayes' Theorem for the technically minded, and it's common sense that when everybody would play a hand the same way, seeing the hand played (that way) gives you no information about the person who played it.

It's possible. I've been mistaken before. Thanks for your feedback.

I believe this is correct. The % chance of him being strong/weak does not change.

Something not quite right here. Given 1 observed shove from 1 shove opportunity he's 3:1 a good player and no information is gained from the top 33% of hands. Given 1 shove from 2 shove opportunities he's 3:2 a good player – is that right? – and no information is gained from the top 17% of hands. Quickly useful.

Thanks for the info, good post. Will help me

Blinds are 100/200 with no ante. You open the pot in early position with a raise to 600, and the player to your immediate left, with 2,400 chips in his stack, calls your raise. One of two things is almost certainly true of this player: either he has a huge hand, probably AA, or he is a very poor tournament player (or quite possibly both).

A simple principle, which David Sklansky calls the Gap Concept, states that it takes a better hand to call than to raise. This is because by raising, you can win the pot by showing down the best hand or by causing your opponent to fold. Given the stack sizes involved in the example above, the caller is forfeiting the opportunity to fold out his opponent’s hand. Either he has a hand so huge that he doesn’t want a fold, or he does not understand a very basic tournament principle.

If this player ends up folding or showing down anything less than a huge pair, you will know that he is loose and weak. Calling off 25% of a stack only to fold the flop is just not something that good tournament players do.

Conversely, if you see a relatively knowledgeable tournament player make a call like this, you can deduce that he likes to get trappy with his big hands, even in spots where it’s transparent what he is doing. When this player does re-raise all in against you, you can call a little more liberally since you have reason to believe he would have just flat called with AA.

For example, suppose you open with 55 and this player moves all in. Based on the pot odds, you need 40% equity to call. If you put him on a range of {88+, ATs+, KTs+, QJs+, AJo+}, your 55 has only 39% equity, so you must fold. However, if you can exclude AA from his range, you now have 41% equity, making a call correct.

I'm not sure where the 40% equity # came from. If there is 3300 in the pot after the short stack shove, and it costs 1800 to call, where does the 40% come from? Thx

Sorry, I guess I should have made more clear that this was a different example than the one above. Suppose you raise, and Villain shoves for some amount such that you need 40% equity to call. That's what I meant- so stack sizes not necessarily the same as in the prior example.

I would say that upon seeing him flip over AK, the player is still equally likely to be the weak or strong type. Discuss.