We are often interested in the question whether two variables are “associated”, “correlated” (I mean the normal English term) or “dependent”. What exactly, or rather in normal words, does that mean? Let’s look at some easy case. NOTE: The example has been updated to reflect a more tangible and sensible scenario (find the old one in the previous commit at Github). Titanic data For example, let’s look at survival rates of the Titanic disaster, to see whether the probability of survival (event A) depends on the whether you embarked for 1st class …