What Can SantaCon Teach Us About Factor Analysis?

An absurdist argument for an important statistical concept.

The Frontier Psychiatrist is a daily health-themed newsletter. Thank you for joining us. Today, it's a little bit of math nerd and a little bit of humor.

Santa is a character who does not really exist. Elves? Also fictional. And yet every year, a strange thing happens in my home city of New York. There is a storm of hundreds who get dressed…strangely. Something odd is happening. There is this weird coincidence. There is a day every year when, in late December, walking around surrounded by a sea of Santa Claus-garbed individuals. On that same day, elves spread up all around the city for reasons unclear. There is additionally, among those dressed as either Santa or dressed as an elf, a sudden onset movement disorder that seems to be rapidly progressive. There is, in a large population of young and healthy individuals, prominent ataxia. This is a disorder in which one has lost the ability to maintain balance and coordination of the body's trunk. It's odd to see it! Dozens, hundre…