The Midsummer Crime Cluster: an investigation

[the rest of SDB’s prob-stat adventure is right here, or grab a paid sub and get all content in your inbox, in its entirety]

For years, I'd thought in passing about putting my July-tragedy-cluster theory to the test…and then decided to think about something else instead. The theory itself – that major-case crime events and other horrific tragedies occur at a higher rate or volume in the middle of July – just sounds old-wives'-talesy on its face, too much so to bother running numbers on. (See also: this Forbes piece from last summer, primarily a lament about mass shootings followed by a shrug emoji on causation.) 

Plus, there's the confirmation bias: because many of the horrors in question land on July 17, my non-Zodiac dad's birthday, that means I'll notice a cluster in a way I wouldn't if the same event density manifested on, say, October 17.

And what would such a test even look like? How much data would I have to gather; how would I really know what any of it meant? Would it turn into a whole foil-hat boondoggle – or worse, I'd become like that satanic-ritual "expert" witness in the West Memphis 3 case who got his certification from the back of Mad Magazine or some damn thing? "Who needs that," I decided. "Nobody cares anyway."