Disclaimer I work at Google. One of the difficulties with using user data to understand society is that the company isn't a static entity. Engineers are always

Disclaimer I work at Google. One of the difficulties with using user data to understand society is that the company isn't a static entity. Engineers are always changing their algorithms for purposes that have nothing to do with the things you're trying to observe. For Google Flu Trends specifically here's a great paper https://gking.harvard.edu/files/gking/files/0314policyforumff.pdf https://gking.harvard.edu/files/gking/files/0314policyforumf...