MORE NUMBERS EVERY DAY

Two professors of marketing and economics launch a well-informed attack on the infallibility of numbers and data.

Popular mathematics books tend to belong to the math-is-fun or how-to-lie-with-statistics genres. Dahlen and Thorbjørnsen, however, offer an ingenious warning that numbers are messing up the world. They are “flirtatious, manipulative, distracting little devils. [They] mislead us and lie. They distort and entice.” The authors deliver a steady stream of anecdotes, studies, and historical events that will unsettle even the most skeptical. Readers who roll their eyes when the authors claim that we perceive odd numbers as masculine and even numbers as feminine must explain why so many professional athletes (mostly men) prefer odd numbers on their jerseys. Even though numbers influence our feelings, identities, and interests, “numbers contain not more information than words but less.” For example, the authors describe an experiment in which subjects read lengthy, information-rich, flattering reviews of a hotel that received an overall rating of 2. Then they read lukewarm reviews of a hotel that was given a high 5 rating. When asked, they preferred the hotel with the higher number, “clearly influenced more by the number than thewritten praise.” To make matters worse, the 21st century has seen an explosion of smartphones, smartwatches, and other logging apps that allow opportunities for self-quantification that Benjamin Franklin could only dream of. Do they work? Studies show that obsessive health monitoring with a Fitbit or Apple Watch improves performance in some users but only slightly. Besides filling the text with suggestions for fending off number mania (“number vaccine advice”), the authors explain that numbers are there to help. That’s why they were invented. However, they are only helpful if we remember that they’re the product of the human mind and therefore almost always subjective, selective, changeable, different in different cultures, swayed by prejudice and emotion, and often simply wrong.

An unnerving but convincing anti-number polemic.