Selfies and shark attacks: Two ways you're very, very unlikely to die. (Photo: Tandem/U.S. Fish and Wildlife Service)
Today's missive covers three of our favorite subjects: innumeracy, psychology and investing. It comes to us courtesy of an article in Outside magazine discussing "the epidemic behind selfie deaths: 259 people died between 2011 and 2017." The article goes on to document some of the risky and foolish things people did while taking a selfie before they were killed, usually by falling from someplace very high.
The article brought to mind shark attacks, which we fear inordinately even though they so are rare that they amount to little more than statistical rounding errors. Meanwhile, we pay almost no attention to mundane but much more lethal threats, such as heart disease and cancer, which claim many, many more lives than sharks, selfies, lightning strikes, terrorists or any of the other freakish events that kill people. Not that you could tell this based on news report or the postings on social media, but the grim reality is that you are something like 35,000 times more likely to meet your maker due to the former than one of the latter.
We fear the bizarre and emotionally resonant, not the commonplace or ordinary. For example, in 2018 there were nine selfie deaths in the U.S. and one fatal shark attack. Meanwhile, the Centers for Disease Control reports that about 610,000 people die each year of heart disease, the No. 1 killer, and almost the same number die from cancer.
Let's try to put these numbers into an accurate frame of reference, and avoid the usual denominator blindness. That is the practice of quoting a single number while omitting any context; in other words, the numerator without the denominator, the two figures needed to give you a percent or fraction.
The epidemic of selfie deaths described by Outdoor magazine was a tragedy involving 259 people who died in a six-year period. Divide that figure into the number of years when those deaths occurred and you get an average of about 43 deaths a year. That's the numerator.
What of the denominator? To create that, we need to come up with a credible estimate of the number of selfies taken each years.
Barry Ritholtz is a Bloomberg Opinion columnist. He founded Ritholtz Wealth Management and was chief executive and director of equity research at FusionIQ, a quantitative research firm. He is the author of "Bailout Nation."
