More on a topic I love, correlation vs causation.
Michael Agger from Slate Magazine has been soliciting ideas for how to use data from online sources such as social networking sites, for making improvements in our lives.
One of the suggestions was The Correlations Project, which proposes:
"I want to see a website that lets me keep track of something simple for a set period of time, and then compares it to a database to search for correlations. For example, over the course of a week or month or year, or even on an ongoing basis, it could ask, "What did you have for breakfast today?" or "What color shirt did you wear today?" or "How many calls did you get on your cell phone today?" Maybe a daily e-mail would remind you to log in with the answers. Then it would compare the answers to other things that are already tracked such as the stock market, phases of the moon, sports scores, etc., and spit out some correlations. It could tell you "On 93% of the days on which you ate eggs for breakfast, the stock market went up." Or, "When the moon is waxing, you are 88% more likely to wear a green shirt than when it is waning." Or, "On days when you get more than 7 phone calls, the Yankees win their games."
Agger explains: "The point of the correlations project, according to the submitter "IronicSans," is to demonstrate the axiom that correlation does not imply causation." He points out the ubiquitousness of coincidences and our tendancy to see links and cause where none exist, and he quotes the case of Paul the Octopus as one example.
A really interesting idea. I have a feeling though that the correlations brought up would become the point in themselves, the site would become a mecca for people believing in its power and accuracy, and in the end it would achieve the complete opposite of what it set out to do!