Correlation and Causation
June 23rd, 2010
As I mentioned in class, your average person on the street is constantly confusing correlation and causation. I see this kind of mistake all the time in news stories, and it makes me absolutely insane. In fact, it happens so often, comic strip writers are now poking fun at us for this all too common error.
It would be great if we could all just live in Colorado and then have healthy weights and be able to avoid the myriad health problems that occur with obesity, but it just doesn’t’ work that way. This is an example of that third variable problem I mentioned. It’s likely that many of the people who live in Colorado have active lifestyles. if you’re active, you’re less likely to be overweight. Active people everywhere have lower rates of obesity – there just may be more of them living in Colorado than in other places. Moving there without also changing your lifestyle won’t solve this problem.
Where have you seen people mistaking correlation for causation?