The implications of mean scaling for the calculation of aggregate consumer elasticities

Mean scaling is a common assumption in the estimation of aggregate consumer elasticities—in particular, expenditure elasticities, but also (implicitly) compensated price elasticities. The assumption is that each household’s income changes in the same proportion as aggregate income. If correct, that implies no bias in the use of aggregate data for estimation of expenditure elasticities. If incorrect, though, there may be substantial bias, …