The Book of Why: The New Science of Cause and Effect (Penguin Science)

by Judea Pearl

The distorting prism of colliders is just as prevalent in everyday life. As Jordan Ellenberg asks in How Not to Be Wrong, have you ever noticed that, among the people you date, the attractive ones tend to be jerks? Instead of constructing elaborate psychosocial theories, consider a simpler explanation. Your choice of people to date depends on two factors: attractiveness and personality. You’ll take a chance on dating a mean attractive person or a nice unattractive person, and certainly a nice attractive person, but not a mean unattractive person. It’s the same as the two-coin example, when you censored tails-tails outcomes. This creates a spurious negative correlation between attractiveness and personality. The sad truth is that unattractive people are just as mean as attractive people—but you’ll never realize it, because you’ll never date somebody who is both mean and unattractive.