A recent conversation with a colleague reminded me of this great website that reminds us of the first law of research. Correlation is not causation. Just because two things happen at the same time or move in the same direction, does not mean one is causing another. This is an easy trap to fall into for both researchers and practitioners who can easily be seduced to locating causes to a clients behavior. Tyler Vigen has developed a fantastic web site full of examples that illustrates this issue. As in the example above, we see the that number of films Nicholas Cage has appeared in correlates with the number of people drowned in swimming pools. Tyler's web site is not aimed at dismissing research or its findings, but to help people think about statistics and data more critically. Check out his website by clicking here for more great examples, And many thanks George, for reminding me to post this!