Let us start with the following problem.

**Problem:** Giovanni is an Italian man, soft-spoken and very calm. He enjoys sharing what he knows and learning new things. He wears glasses and is particularly fond of logic puzzles. Is it more likely that Giovanni is a high school teacher or a metal worker?

Let us start with a gut answer: given the description of Giovanni, we can easily see him as a teacher, he really fits our stereotypical description. At the same time, we want to go a little beyond the gut answer: is there a way to give a more “mathematical” or “scientific” assessment? We can split the problem at hand into smaller ones: we want to figure out how could we come to an answer, what data we have and how can we get from the data to the answer.

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