Correlation Does Not Mean Causation

The most important lesson of the school year

If I could gift my students with only one single concept that they could take from my class and bring into the real world, it is this one: correlation does not mean causation.


Why does this matter?

So often, the attention-seeking media will infer a causal relationship to make better story. An informed population must be able to recognize this gross negligence.

  • “Wearing clothing that promotes alcohol use increases a young person’s chance of binge drinking”

  • “Margarine consumption linked to divorce, recent study reveals”

Image from Spurious Correlations by Tyler Vigen


I use a few ridiculous claims to introduce the concept to students:


Ice cream sales and shark attacks

There was a study that was done that found a strong correlation between the ice cream sales and number of shark attacks for a number of beaches that were sampled.