The Importance of Uncertainty Analysis in Predictions

Physicists knew that the electromagnetic radiation coming from a high voltage power staunction is usually very low frequency indeed, you might get some radio waves. The better explanation as it turns out is that people who live close to power staunctions live in houses where the land value is lower and they can't afford better health care. So this is a case where we can have a very good correlation between two things but one does not cause the other. And that third factor actually means that you can't use that relationship to make useful predictions.