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#06 - Definition of expected utility theory

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Article written by
Juan Jesús Millo

What is the expected utility or interaction cost?

That moment you're sitting on the couch, with a TV channel that's not very entertaining, but it's not the worst either, and you think, "What will be on the other channels?" There are two terms that will determine the action you're going to take, the interaction cost and the expected utility. Let's calculate them.

Interaction cost theory

You are quite far away from the remote, so you start calculating in your subconscious how much mental and physical effort you need to put in:

You need first to locate where the remote is, move your head to get a better angle of vision, locate the remote, see what you are doing with one arm in case you have it occupied or not, calculate the distance in case you get there or you need to use another movement, think that you are in a quite uncomfortable position and that you have to move to reach it, move to get your arm there, raise your arm, think how to grab it, and finally grab it. We haven't even interacted with the control system, do you understand how it works?

The cost of interaction is the total sum of all the mental and physical efforts, but this value cannot work without first having calculated the expected utility.

Before we execute this series of steps, we think and calculate this one, which is nothing more than the expected benefit minus the expected interaction cost.This is the reason why many times we are lying on the couch and we do not even get up to take control, because the expected utility would be negative because the expected benefit is less than the interaction cost.

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