Jeffrey Rosenthal has a personal stake in this question. He was born on a Friday the 13th, and every time someone calls the date unlucky, it feels a little bit personal. So he did what a statistics professor does: he got access to a massive database of unexpected deaths from the Ontario coroner's office and checked whether the date actually holds up.

The result surprised even him in a few specific ways. Friday the 13th itself came in lower than the yearly average, but a nearby date showed a small uptick, one Jeffrey has a theory about involving timing and reporting delays. He also ran the same test on Halloween, expecting a similar pattern, and found something worth explaining.

The real discovery came somewhere else entirely: a specific multi-week window each winter where unexpected deaths spike well outside normal statistical variation. Jeffrey explains the medical reason behind it, and it has nothing to do with luck.

Topics: is Friday the 13th unlucky, statistics and superstition, confirmation bias, winter death rates, Ontario coroner data

GUEST: Jeffrey Rosenthal | http://probability.ca

Originally aired on 2026-09-11