Q1: How do I determine if a call is +EV?

Answer: Compare the payoff to the chance of winning.

* Example 1: No cards left to come

Heads-up on the river, Villain shoves $50 into a pot of $100. We think that we have 40% equity against his range. This call is +EV because our pot odds are 3:1 and the odds against us winning are 1.5:1.

* Example 2: Cards left to come, not calling all-in

Heads-up out of position on the flop, we check to Villain who bets $5 into a pot of $10. We have the nut flush draw, and we think if we hit on the turn, on average we can extract another $15 from this Villain. Our implied odds are 6:1 and the odds against us hitting are about 4:1, so this call is +EV.

* Example 3: Cards left to come, calling all-in

We open raise 77 on the button for 4x the big blind, the small blind shoves to 15bb, and the big blind folds. Since we are calling 11bb to win 20bb, our pot odds are 20:11 or about 1.8:1. We think we have about 40% equity against his range. This call is +EV since our pot odds are 1.8:1 and we are about 1.5:1 against to win.