Quote:
The formula for Aggression Factor (AF) is:
AF = ( Bets + Raises) / Calls
We don't need to calculate it. Just know this. Having an AF of 2 (twice as many bets/raises as calls) is a reasonable breaking point. AF's > 2 are generally aggressive, and AF's < 2 are generally passive.
You can use a HUD to gather this information precisely, or you can do the analogue "note taking" version. Simply mark on a piece of paper during the first 30 hands while you're at the table which villains open and how they play postflop. Mark when they limp or call preflop, and mark when they bet/raise or call postflop. If a villain bets or raises about twice as often as he calls (AF = 2), think of that as "honest" or neutral aggression, betting good hands and folding bad hands. Villains who bet or raise three times more often than calling (or more, AF > 3), they are aggressive and are often firing cbets, bluffs or semi-bluffs. Villains who bet or raise about as often as they call are passive (AF ~ 1), typically calling stations who chase bad hands and don't bet their good hands often enough.
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