Correlation vs. Causation

What does it actually mean when scientists notice a correlation between events in their study?  It is possible that one event may have caused the others, but only further research can determine if there is cause and effect or just coincidence.  Often journalists will report a correlation as if there is cause and effect, without further evidence to back them up, and this can lead to wrong conclusions.  One of the most famous of these mistakes was in 1952, when scientists noticed that the number of polio occurrences was correlated with ice cream consumption.  While ice cream sales dropped, the number of polio cases did not change.

 

In this video, we explore possible explanations for a correlation, showing that more research is necessary to draw a conclusion.