MDF (Minimum Defense Frequency)
What it means
The part of your range you have to continue with (call or raise) facing a bet so that a bluff with any two cards doesn't automatically win chips: pot / (pot + bet) = 1 − α. It applies to the RANGE that reaches that point, not to each hand.
Example
You face a 6 bb bet into a pot of 9: MDF = 9 / 15 = 60%. If you fold more than 40% of your range, any bluff wins.
Also called: minimum defense frequency · defensa mínima
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