I remember when I first heard about Google Flu that I felt it seemed like magic. Now though it’s accuracy is being called into question. From the authors of the main paper:
“Big data hubris” is the often implicit assumption that big data are a substitute for, rather than a supplement to, traditional data collection and analysis.
Hubris is a bit strong, but the issues with Google Flu point out its achilles heel: Reliance on self-reported data.
Syndromic surveillance can be a great tool to predict outbreaks, but when non-medical audiences are doing the surveillance the system breaks down.