An analysis by a team from the University of California, Davis, MIT and Yale suggests that households that buy a fuel-efficient vehicle tend to compensate for that purchase by buying a bigger, more powerful second vehicle. This unintended effect could erode goals of fuel economy standard policies by up to 60%. The researchers explored the phenomenon of attribute substitution in the context of multi-vehicle households. Attribute substitution is the trading off of the particular attributes of one product with the attributes of another—ordering a side of fries with a diet soda, for example, or decreasing the size of other televisions in a home after buying a larger screen version. The idea that products can act as complements or substitutes is commonplace […]