Are Homicides up 533% in Portland?
Technically, kind of. But use of this statistic is a classic case of the base rate fallacy.
I’ve long stopped expecting my elected officials to be 100% honest. It’s disheartening, and makes me a cynic for sure, but I’ve accepted that part of their job is to periodically sell their souls and carry the party talking points, even when they know they’re spreading misinformation. I certainly do not respect them for doing this, but whatever. They do it.
This morning I woke up to an email from my representative, Congressman Rob Wittman. He’s an educated man — he has a PhD in a scientific field, and I imagine he knows a thing or two about statistics. Nevertheless, he sent an email parroting GOP talking points and statistics about rising crime rates.
One statistic stood out as particularly outrageous:
“Homicides are up 533% in Portland…”
On first glance, one might assume that Portland has devolved into total anarchy and outright war. But the actual numbers tell a different story. This is where we learn about the base rate fallacy.
