Tip #10: The Independent Chip Model (ICM)

The Independent Chip Model (ICM) should be one of your best tools when you reach the bubble and end game

Sit and Go professionals often use a mathematical model known as the ‘Independent Chip Model‘ or ‘ICM’ to make better decisions at the bubble. This converts your chip stack into ‘prize pool equity’ – which you then use to balance risk and reward for all-in confrontations. We recommend that you learn and implement this method – even if you do not intend to use it yourself it is important that you understand how it works. The reason is that many of your opponents will be using it – and understanding how they make decisions will help you to assign hand ranges to them.

Key to understanding ICM is to grasp the concept of ‘prize pool equity’. In a typical SNG tournament with payouts of 50% / 30% / 20% the number of chips in your stack at the bubble is not directly proportional to the average amount you will win – should the tournament be played 100′s of times over.

For example of 10,000 total chips you may hold 9,700 and each of 3 opponents may hold just 100 each. Yet the most you can win is 50% of the prize – and one opponent will turn their 100 chips into 30% of the prize pool. While the effect is usually more subtle than this the concept is constant, as you add more chips to your stack their ‘average value’ goes down in other words the chips that you lose are more valuable than the chips you win.

Here is an example of how ICM might help you to make a decision. While the math can seem complicated there are many poker tools which help you to learn this. It will become second nature in no time at all with the help of tools like SNG Wiz (check this article: best SNG softwares).

In this example you are playing on a $10+1 SNG on Poker Stars, with a $100 prize pool up for grabs in a 50% / 30% / 20% format. There are only four players left, each one with 1000 chips. Ignoring who has the blinds and skill differences the ‘average’ that each player will win over hundreds of situations is $25 – this is your ‘prize pool equity’.

• Player A: 1000 Chips. Prize pool equity = $25
• Player B: 1000 Chips. Prize pool equity = $25
• Player C: 1000 Chips. Prize pool equity = $25
• Player D: 1000 Chips. Prize pool equity = $25

Now player A pushes all in and player B calls and loses the hand. Here is the equity after the hand (calculated on SNG Wiz):

• Player A 2000 Chips. Prize pool equity = $38.33
• Player B 0 Chips = $0 -> eliminated
• Player C 1000 Chips. Prize pool equity = $30.83
• Player D 1000 Chips. Prize pool equity = $30.83

Looking at the prize pool equity after the hand shows that player B risked his $25 by calling the all-in from player A – yet his reward (in equity terms) was only an additional $13.33. Even though B felt that his hand had good chances against player A’s range, he was risking $25 to win $13, actually laying odds against himself.

This explains why it may be ‘correct’ to push all-in with a wide range at the bubble, but not to call when someone else has raised. Also note that the equity of players C and D went up, since they are now guaranteed 20% ($20) and have chances of winning.

ICM is a powerful model and we recommend that you take the time to learn how this applies to various situations. The free trial of SNG Wiz is a great place to start. We will discuss more about ICM in future SNG tips.