Tournament Strategy – the Independent Chip Model (part 1)

The Independent Chip Model, abbreviated as ICM, is an integral part of tournament strategy for all those more or less knowledgeable in this respect. The ICM is meant to establish the value of an individual tournament chip in any given moment in a poker tournament, and because it answers one of the most fundamental questions and biggest dilemmas of poker tournament action, it is indeed extremely helpful for those who know how to put it to use.

Let’s not cut ahead of the chase though, and let’s take a closer look at what the ICM really is and what problems it’s likely to sort out.

Every tournament player knows that despite the ongoing indoctrination of players in regards to the value of aggression, in a poker tournament, sometimes it makes perfect sense to tighten up in order to make it past a money bubble or a payout jump. Most tournament strategy articles recommend that one loosen up instead and take advantage of other people’s tightness, but that is simply not always the optimal way to approach the problem. The ICM will help you decide when it’s ok to tighten up and when you should go for all the marbles so to speak, by helping you determine the actual value of the tournament chips in your possession. Simply counting one’s chips is never really helpful, because the value of a single tournament chip varies wildly through the event. Wait a minute…what’s that? The value of a tournament chip varies through the game? That’s correct. It does and that’s exactly why it’s so darn difficult to figure out when you should resort to aggression on the bubble and when you should turtle up.

The best way to understand how and why the value of a tournament chip changes is through a simple example. Suppose you’re in a $10 SNG, with 9 other players, sitting on an initial stack of 1k chips. The payout structure gives the winner $50, the runner-up $30 and the 3^rd place finisher $20.

At this point, it’s fairly easy to say that your 1k chips are worth exactly $10 (the amount of the buy-in). Once the action gets going and you manage to sneak into the money with 1k chips still to your name, you can say that your 1k chips are worth twice as much: $20. The thing is though that even if you have 100 chips as the bubble bursts, those 100 chips are still worth $20. If you make it all the way in the tournament and win, you end up with 10k chips worth $50, which means that your 1k batch is worth only $5 at that point.

The ICM works based on two variables: the payout structure, which is a given of course, and the stack sizes of players, which is a way for the model to determine the probability of each of the players finishing 1^st, 2^nd, 3^rd etc.

While nailing down the odds of winning for each player is fairly simple, the calculations get a lot more intricate for the probability tied to 2^nd, 3^rd, 4^th etc…places.

More on how you can use the ICM in making actual decisions at the virtual green felt, in the second part of this article.