AI in Action: How algorithms can analyze the mood of the masses

With billions of users and hundreds of billions of tweets and posts every year, social media has brought big data to social science. It has also opened an unprecedented opportunity to use artificial intelligence (AI) to glean meaning from the mass of human communications. The University of Pennsylvania's Positive Psychology Center, for example, uses machine learning and natural language processing to sift through gobs of data to gauge the public's emotional and physical health, including levels of depression and trust, and several personality traits. That's traditionally done with surveys. But social media data is cheap and abundant.