“Trump is a man who polarizes opinion: you suspect that if he said ice cream was a pleasant treat on a sunny day, it would lead some Americans to refuse to eat anything but ice cream while others protested loudly outside ice cream parlors. Campbell, who around the same time explained: “The more any quantitative social indicator is used for social decision-making, the more subject it will be to corruption pressures and the more apt it will be to distort and corrupt the social processes it is intended to monitor.”” Economists tend to cite their colleague Charles Goodhart, who wrote in 1975: “Any observed statistical regularity will tend to collapse once pressure is placed upon it for control purposes.” (Or, more pithily: “When a measure becomes a target, it ceases to be a good measure.”) Psychologists turn to Donald T. The Nobel laureate economist Friedrich Hayek had a phrase for the kind of awareness that is hard to capture in metrics and maps: the “knowledge of the particular circumstances of time and place.” Social scientists have long understood that statistical metrics are at their most pernicious when they are being used to control the world, rather than try to understand it. Sometimes you have to be there to understand-especially when a situation is fast-moving or contains soft, hard-to-quantify details, as is typically the case on the battlefield. The Data Detective: Ten Easy Rules to Make Sense of Statistics And tenth, we should keep an open mind, asking how we might be mistaken, and whether the facts have changed.” Ninth, we should look under the surface of any beautiful graph or chart. Eighth, we should pay more attention to the bedrock of official statistics-and the sometimes heroic statisticians who protect it. Seventh, we should ask tough questions about algorithms and the big datasets that drive them, recognizing that without intelligent openness they cannot be trusted. Sixth, we should ask who is missing from the data we’re being shown, and whether our conclusions might differ if they were included. Fifth, we should look behind the statistics at where they came from-and what other data might have vanished into obscurity. Fourth, we should look for comparisons and context, putting any claim into perspective. Third, we should look at the labels on the data we’re being given, and ask if we understand what’s really being described. Second, we should look for ways to combine the “bird’s eye” statistical perspective with the “worm’s eye” view from personal experience.

First, we should learn to stop and notice our emotional reaction to a claim, rather than accepting or rejecting it because of how it makes us feel. “I’ve laid down ten statistical commandments in this book.

Tim harford the data detective