Tuesday is the 67th anniversary of the rumored alien crash-landing in Roswell, New Mexico. But extraterrestrial aviators have been rather busy in the last few decades.
The National UFO Reporting Center has received about 90,000 reported sightings of UFOs in the last 40 years, according to the Economist. That's about six per day—with the majority happening on Fridays, in the West, and during, um, drinking hours.
The fact that this graph is going viral online today suggests many are persuaded by the correlation. It would irresponsible for me, as a statistical analyst, to not point out the problems with it. And so, for the Roswell fans out there, I present three veins of countervailing interpretation:
1. The correlation is weaker than it appears. Utah, the state with the lowest beer consumption by far, has a higher share of UFO sitings than North Carolina, the state with the highest beer consumption. Washington, the state where you're most likely to report a UFO, drinks less alcohol than all but six states. There is more to the story than alcohol, sheeple.
2. We have several omitted variables, including direct line-of-sight to the sky and light contrast. It's plausible that people don't see UFOs while they're working or sleeping because ... they're working in-doors and completely unconscious. What the Economist calls "drinking hours" are also the hours we're most likely to be outside looking at anything bright contrasting with the dark sky.
3. The direction of causality isn't clear. As I wrote earlier today
Compelling graph. But have you considered aliens *choose* to fly over drunk people to destroy witnesses' credibility? pic.twitter.com/43UiZ607Ag— Derek Thompson (@DKThomp) June 28, 2014
Other theories, counter-theories and photo evidence are welcome in the comment section...