Definition of liability
In poker, when we talk about a passive player, we are talking about a player who generally does passive rather than aggressive actions. Folding, limping, folding and calling are passive actions. Betting, raising, 3bet and 4bet are aggressive actions. A passive player is a player who will mostly do passive actions. An aggressive player might check-raise on the flop. The passive player will check-call his draw. The only time the passive player will raise is when he has the nuts.
How to identify the passive player?
If you have a tracker like Poker Tracker 4 or Xeester, you will be able to display a statistic called "Aggression Factor" in your HUD. This is usually a good indicator of how aggressive a player is. The stat will ratio the player's passive and aggressive plays and show an aggression rating. To identify aggressive players, you should know that 2.0 of "aggression factor" is the 0 degree of aggression. At 2.0 you are "normal" aggressive. At more than 2, you are considered aggressive and at less than 2, you are considered passive. You will sometimes see players with aggression indicators of 0.7. Against such a passive player, give full credit to his aggressive games!
