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Datasets that change the odds you exist

Stats for dangerous situations

It's October 1962. The Cuban missile crisis just happened, thankfully without apocalyptic nuclear war. But still: Apocalyptic nuclear war easily could have happened. Crises as serious as the Cuban missile crisis clearly aren't *that* rare, since one just happened. You...

Using axis lines for good or evil

add them only if they mean something

Say you want to plot some data. You could just plot it by itself. Or you could put lines on the left and bottom. Or you could put lines everywhere. Or you could be weird. Which is right? Many people...

Prediction market does not imply causation

Unless you're careful, conditional prediction markets have all the same problems as observational studies.

We all want to make good decisions. But it’s hard because we aren’t sure what’s going to happen. Like, say you want to know if CO₂ emissions will go up in 10 years. One of our best ideas is to...

The conspiratorial Monty Hall problem

What if you and Monty decide to cheat?

The Monty Hall problem has now been a pox on humanity for two generations, diverting perfectly good brains away from productive uses. Hoping to exacerbate this problem, some time ago I announced a new and more pernicious variant: What if...

Why ‟controlling for a variable” doesn't (usually) work

It's just adding a variable to a regression.

I’ve always seen cathedrals as presenting a kind of implicit argument to atheists. Something like: God must exist, because otherwise it would have been insane for people to build this:

Social dynamics of bluetooth speakers

A mathematical model of who turns on their bluetooth speaker at the beach.

Say you're at a park or a beach. How many people will have bluetooth speakers on? It seems to me there are three types of people: The main characters always turn on their speakers regardless of what anyone else is...

It’s perfectly valid for a trait to be more than 100% heritable

What heritability really is: A fluid statistic that changes whenever society changes.

All psychological traits are heritable. This is the best replicated finding in all of behavioral genetics. Some recent numbers include: Religiosity: 44% Schizophrenia: 79% Big five personality traits: ~40% But what, exactly, does "heritability" mean? I used to have a...

Simpson's paradox all the way down

Visualizes Simpson's paradox, and shows how it's a deeper problem than many people realize.

It's hard to get into Oxford. Is it easier if your parents are rich? In 2013, The Guardian showed noticed something disturbing: Students from (expensive) independent schools were accepted more often that students from state schools (28% vs 20%). Of...

The simplest possible way to convert Celsius and Fahrenheit

If you can switch the order of two numbers, you can convert temperatures.

This is a new way to convert temperatures between Celsius and Fahrenheit. It’s not the most accurate method, but it’s surely the easiest.

Making the Monty Hall problem weirder but obvious

It's this simple: Do you want what's behind one door or the other nine?

Here’s an Obvious Problem: There are 10 doors. A car is behind a random door, goats behind the others. Do you want what’s behind door 1, or what’s behind all the other doors? That’s easy, right? Well, how about the...