What is a spurious correlation?
In statistics, a spurious relationship or spurious correlation is a mathematical relationship in which two or more events or variables are associated but not causally related, due to either coincidence or the presence of a certain third, unseen factor.
Here is an example I created:
What does this show?
This is real data, I did not make this up. At first glance of the data, most could just say ‘Well, looks like we have a homeless problem in Seattle because of the all the tv’s connected to the internet!’. In actuality, homelessness in Seattle and tv’s connected to the internet in the U.S. are associated but they are not causally related.
What does this mean?
In layman’s terms, this means that though they seem like they are connected, they are not. This can be due to something called a confounding variable, or an unseen variable. For example, homelessness could probably be increasing as the cost of living in Seattle increases. Homelessness could also be increasing as the price of heroin gets lower.