Economists have devoted substantial attention to firms' supply of variety, but little to consumers' demand for variety. Employing the framework of home production, we trace differences in demand to differences in the opportunity costs of activities, which are associated with investments in human...

The American Time Use Survey 2003-15, the French Enquête Emploi du Temps, 2009-10, and the German Zeitverwendungserhebung, 2012-13, have sufficient observations to allow examining the theory of household production in much more detail than ever before. We identify income effects on time use by...