Independent Chip Model
In poker, the Independent Chip Model (ICM) is a mathematical model used to calculate a player's overall equity in a tournament. The model uses stack sizes alone to determine how often a player will finish in each position (1st, 2nd, etc.). A player's probability of finishing in each position is then multiplied by the prize amount for that position and those numbers are added together to determine the player's overall equity.
The term ICM is often misunderstood to mean a simulator which helps a player make decisions in a tournament. Such simulators often make use of the Independent Chip Model but are not strictly speaking ICM calculators. A true ICM calculator will have the chip counts of all players as input and each player's equity as output.
The ICM can be applied to answer specific questions, such as:
- What range of hands can I move all in with, considering the action so far and the stack sizes of the other players still in the hand?
- What range of hands can I call another player's all in with, and should I just call or move all in over the top, considering all the stacks still in the hand?
- If we are discussing a deal, how much money should each player get?
References
Further reading
- Harrington, Dan; Robertie, Bill (2014). Harrington On Modern Tournament Poker. Two Plus Two Publishing LLC. ISBN 1-880685-56-6. Harrington discusses the ICM on pages 108-122.