Playing aggressively with marginal hands

Could someone please explain to me both when and why this can be +EV? I have a hard time understanding why we would want to put in more bets when we are behind most of the time.

[SheridanCat]

Well, it's not a good idea to blindly throw in bets with hands that are truly marginal. But in all things poker, what is truly marginal depends on the situation.

One advantage that somes to mind is "fold equity". That is, by betting (or raising) you have the added possibility that your opponent will fold. Say you have a hand that you think is behind, but you expect your opponent's hand is also marginal. A bet or raise as a scary board may win the pot.

Additionally, you might run a blind steal with hands that are generally not that great.

In a tournament situation, you might find yourself so short-stacked that a marginal hand is good enough to play aggressively.

I'm sure there are other situations I can't think of at the moment. But, generally, we strive to start with hands that are better than our opponents and play aggressively when we think we have an edge.

Regards,

T

[4_2_it]

One that T didn't mention is lowering your raising and calling standards when you have position and know you can out play your opponents post flop. This is always +EV in NL.

It makes a difference if it's limit or no limit. If you've identified tight players and you have position, play your position (think that your aggression is related to your position, not your hands).

How is it +EV? SSHE: " To calculate expectation mathematically, you must take an average of all the possible results, weighted by the likelihood of each one. "

Just for an example, let's say that you're attempting to blind steal in position. If it's folded around to you, and you bet 2x the BB, the possible results are that the blinds fold, one or both calls, one or both raises. If you're facing a raise, you probably will fold your hand, depending on the raise. If one or both calls, the outcome depends on the flop.

Let's say that you expect to win with a raise against the blinds 2 out of 3 times. You will fold to a raise. If called, you expect to win 1 out of 4 times (made that up, depends on the hand, etc). Since it's preflop, we can count in terms of blinds, or bets. SB=1 bet, BB=2 bets, your raise = 4 bets. You are wagering 4 bets to win 3.Doesn't sound so good. But if you expect to win 2 out of 3 times, then

EV=1(3) + 1(3) + 1(-4)
EV= 3 + 3 - 4 = +2 (I think)

But actually, your EV may be better than this since, if you're just called, you may actually end up winning the hand and more bets.

I hope I did the math right. The point is, depending upon the likelihood that you could pick up the blinds, or even extra bets if there's limpers who will fold to an aggressive raise, you don't have to succeed every time for it to be +EV. If you base your decision for when to make such moves on the tightness/weakness of your opponents, you increase the likelihood that it will be successful.

Criticisms of my math and explanation welcome.