Natural Experiments

Source: David Friedman’s Substack
by David Friedman

“One argument offered for laws against pornography is the claim that it leads to violence against women. A counter argument is that it actually decreases such violence …. Economist Todd Kendall found an ingenious way of using a natural experiment to find out which was true. Access to the internet makes pornography more readily available …. Kendall looked at the data to see whether, controlling for other variables, increased access to the net correlated with an increase or decrease in rape. The answer was that it correlated with a decrease, about a ten percent drop in rape for a ten percentage point increase in internet access. There was no similar relation for murder, which suggests that the result is not simply picking up the effect of some third variable that happens to correlate with both internet access and violent crime.” (06/04/24)