You might not believe in astrology or certain facets of behavioral science, and that's fine! But statistical evidence shows that a strikingly large number of serial killers were born in the month of November. And, hey, look, it's November right now!
A study published by researcher Jan Ruis back in 2006 explores the phenomenon in depth. The study uses statistical and behavioral analysis to understand the wisdom of certain astrologers as they pertain to serial killer behavior. The conclusion? "[B]ased on the two datasets, some of the claims of astrologers cannot be rejected."
But the most easily identifiable data-point that comes from the analysis is simply that most mass murderers are born in November. Here's a more succinct summary of the data from UberFacts: "Seventeen serial killers were born in November, compared with an average of nine for other months, out of a total of more than 100 in the study. Those born in November are most likely to believe they get a raw deal. A 2005 study found that they grow up to be the most pessimistic."
Sure, we can point to the stars to figure out why this happens — but ultimately no one really knows.
The good news is that Bjork and P. Diddy were also born in November. So don't worry about this too much if you're going to pop out a baby this month. There's a chance they'll turn out just fine.