Chris Lane, U.S. tourism boycotts, and large relative risks on small probabilities

Jeff Leek

Chris Lane was tragically killed (link via Leah J.) in a shooting in Duncan, Oklahoma. According to the reports, it sounds like it was apparently a random and completely senseless act of violence. It is horrifying to think that those kids were just looking around for someone to kill because they were bored.

Gun violence in the U.S. is way too common and I’m happy about efforts to reduce the chance of this type of event. But I noticed this quote in the above linked CNN article from the former prime minister of Australia, Tim Fischer:

People thinking of going to the USA for business or tourist trips should think carefully about it given the statistical fact you are 15 times more likely to be shot dead in the USA than in Australia per capita per million people.

The CNN article suggests he is calling for a boycott of U.S. tourism. I’m guessing he got his data from a table like this. According to the table, the total firearm related deaths per one million in Australia is 10.6 and in the U.S. 103. So the ratio is something like 10 times. If you restrict to homicides, the rates are 1.3 per million for Australia and 36 per million for the U.S. Here the ratio is almost 36 times.

So the question is, should you boycott the U.S. if you are an Australian tourist? Well, the percentage of people killed in firearm related deaths is 0.0036% in the U.S. and 0.00013% for Australia. So it is incredibly unlikely that you will be killed by a firearm in either country. The issue here is that with small probabilities, you can get huge relative risks, even when both outcomes are very unlikely in an absolute sense. The Chris Lane killing is tragic and horrifying, but I’m not sure a tourism boycott for the purposes of safety is justified.