I almost hate myself for writing this.
Freakonomics is a cliché. And far too famous for its “the reason that crime dropped in the United States in the 90s is the abortions that were happening in the 70s”.
Nevertheless, for most of us, Freakonomics is an awesome way to be introduced to:
- economics; and
- general skepticism for statistics
Because we should all be skeptical of statistics. And, for that matter, heavily skeptical of rhetoric. Particularly when either are used by:
- Activists; and
- People in general.
Because statistics are just observations of correlations between two types of thing happening. Cause is applied by interpretation. For example:
The decrease in the crime rate happens 20 years after the increase in the abortion rate. Those two events are correlated once you take into account the impact of time. That is the observation.
But the causation is interpretative: “The increase in abortion caused the decrease in the crime rate” – is the opinion of the statistician about the relationship between the observations. At which point, the recipe calls for some heavy rhetoric to justify the causation assertion.
I say that because the politicians at the time claimed that the lowering of the crime rate was the result of better policing.
No doubt there were environmentalists that claimed it was the result of global warming. The journalists just claimed anything. And the activists probably put it down to the devastating effects of AIDS on those portions of the population that were having so much sex in the 70s.
Ah statistics: so slyly subjective.