Google retools its flu prediction engine – after getting it wrong
The Wall Street Journal - 10/31/2014
Until recently, Google Flu Trends was the poster child for the promise of big data as a tool for social good. Companies from Nielsen to large telcos are offering up their customer data to experts who can mine it for clues about public health and social unrest. The Flu Trends algorithm uses data derived from Google search terms to predict flu outbreaks in 29 countries. The company recently added Dengue Trends to its roster of prediction services.
But Google Flu Trends turned out not to be the best representative of big data for social impact. While Google’s model was relatively accurate initially — the company first launched it in 2008 — by the 2012-2013 season, its predictions were far off the mark. Google Flu Trends overshot the number of flu cases 95% of the time during that season, according to David Lazer, a Northeastern University computer science professor. Google updated its algorithm the following year, but it still overshot by 75%, Lazer said.