Pursuits
Not All Fuel Efficiency Is Equal: Understanding the Miles-Per-Gallon Illusion
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As the Detroit auto show gets underway, fuel efficiency, as always, will be a much-touted feature when automakers pitch new vehicles. Yet miles-per-gallon claims can confuse the uninitiated. Sometimes, as in the case of upgrading vehicles, mpg values can be irrelevant.
Duke Professors Richard Larrick and Jack Soll first described (free sign-in required) this concept in a 2008 Science article. Richard Thaler and Cass Sustein have continued the conversation at their Nudge blog. The mpg illusion happens mainly because our brains are not very good at doing quick math. We make fast, usually incorrect, assumptions about the meaning and usefulness of numbers.