OUTNUMBERED

Further frighteningly convincing research about the data infiltrating our lives.

Experts regularly warn us that today’s digital technology can extract our innermost secrets. In this ingenious addition to the genre, Sumpter (Applied Mathematics/Univ. of Uppsala, Sweden; Soccermatics: Mathematical Adventures in the Beautiful Game, 2016, etc.) agrees that there is some truth in this assessment but also serious limitations. The book, less a polemic than a combination of investigative journalism and (mostly) painless mathematical lessons, explains how social media, search engines, and merchants extract our opinions and manipulate them with a set of rules called an algorithm, which can often reveal our tastes, personality, and politics. Readers comfortable with ads tailored to previous purchases may flinch to learn that every mouse click such as a “like” under a photo, joke, or film clip enters a massive digital archive that reveals an unnervingly accurate portrait of the clicker. “Unlike our friends—who tend to forget the details and are forgiving in the conclusions they draw about us—Facebook is systematically collecting, processing and analyzing our emotional state,” writes the author. “It is rotating our personalities in hundreds of dimensions, so it can find the most cold, rational direction to view us from.” Persuading us to buy stuff seems benign, but the internet also teems with fake news scientifically designed to influence our votes. Sumpter returns repeatedly to the surprise victories of Donald Trump and Brexit. Wielding his mathematical tools, the author explains how algorithms deal with big data, and it turns out there is less there than meets the eye. Polls only calculate the odds of an event; they can’t “predict” anything. True believers lap up fake news, but it has a barely detectable effect on changing the average reader’s mind.

Americans readers should look past the Britishness of the text to find a deliciously insightful, mildly skeptical analysis of internet data manipulation.