Metric and Scale Design as Choice Architecture Tools

Interest is increasing in using behavioral decision insights to design better product labels. A specific policy target is the fuel economy label, which policy makers can use to encourage reduction in carbon dioxide emissions from transport-related fossil-fuel combustion. In two online experiments, the authors examine whether vehicle preferences can be shifted toward more fuel-efficient vehicles by manipulating the metric (consumption of gas vs. cost of gas) and scale (100 miles vs. 15,000 miles vs. 100,000 miles) on which fuel economy information is expressed. They find that preference for fuel-efficient vehicles is highest when fuel economy is expressed in terms of the cost of gas over 100,000 miles, regardless of whether the vehicle pays for its higher price in gas savings. The authors discuss the underlying psychological mechanisms for this finding, including compatibility, anchoring, and familiarity effects, and conclude that policy makers should initiate programs that communicate fuel-efficiency information in terms of costs over an expanded, lifetime scale.