Saturday Morning Breakfast Cereal posted a comic today that does a good job of illustrating a metaphor I like to use. “Sharks at the Beach.” The shark bit comes in at the little red vote button. The comic is about how bad people tend to be at evaluating risk, mixed with a dash of political commentary about the “War on Terror.” Educating a person about statistics or even simple probability can be a big help in getting them to understand the real risks in life.
For those who haven’t read my use of the “Sharks at the Beach” metaphor before, it’s an illustration I like to use about bias in evaluating risk. A lot of people tend to fear dramatic, spectacular, or otherwise “showy” risks, like being attacked by a shark at the beach. At the same time, they generally ignore the mundane risks of everyday life, like getting into a fatal car accident while driving to the beach. An encounter with a shark would be quite dangerous to life and limb, but such encounters are unlikely to happen, especially for people who don’t live near the coast. Going on an occasional beach vacation isn’t likely going to lead to a shark attack.
Opposite that, for many people, driving is a frequent activity. A single car trip isn’t likely to end badly. Because we have frequent safe trips, many people end up dismissing the danger and file driving as a “safe” activity, while risks with sensational results are deemed “dangerous,” even if the hazard is unlikely. A lot of people end up extending this way of thinking to black-and-white extremes and can end up insulating themselves due to overhyped mass media scares or neglecting basic safety measures in everyday activity because they don’t perceive the risk. One example of the former I recall hearing on NPR was a woman’s mother who, a few years after 9/11, was terrified of her daughter traveling by airplane because her long blonde hair would make her stand out as a target for being taken hostage by terrorists. Despite terrorist incidents, travel by airplane is still pretty safe compared with other methods of long distance travel.
The political aspect in this is the cost/benefit ratio of many anti-terrorist measures. As I see it, every new anti-terrorist countermeasure involves some cost to innocent people, and there’s going to be a point where that cost outweighs the benefit of preventing attacks. The law of diminishing returns applies. Spending a little more effort at airports looking for suspicious activity and potential bombs is perfectly understandable. On the opposite extreme, there’s panicky civilians and racially-profiling security who cause trouble every time someone brown-skinned or dressed up in exotic attire does something vaguely odd but innocent (or for merely existing) and act on it. Too easily this ends up as theater where innocent people are dragged off the plane by security, presumed guilty by the public, and the troublemakers are effectively rewarded for their paranoia. More sensitive detection means more risk of false positives and associated costs. With all the disproportionate fear being spread around by demagogues, who needs terrorists?