More accountability for big-data algorithms

From time to time, scientific equations appear in the media and claim to distil the perfect way to make a cup of tea or identify the most miserable day of the year. Not according to the critics who line up on social media and blogs to complain about the pseudoscience and the commercial interests of those often involved. Some of that scrutiny deserves a more important target. In a short space of time, the equations of big-data algorithms have permeated almost every aspect of our lives. A massive industry has grown up to comb and combine huge data sets -- documenting, for example, Internet habits -- to generate profiles of individuals.