SPECTRAL WELFARE COST FUNCTIONS

If preferences are not time-separable, economic agents care not only about the magnitude of fluctuations in consumption but also about the persistence and other temporal characteristics of those fluctuations. This paper extends and develops the theory of spectral utility functions, which measure utility frequency by frequency, to illustrate the interaction between consumption volatility and time-non-separable preferences. To highlight the economic implications of the interaction, spectral welfare cost functions are developed to provide a quantitative measure of the importance to economic agents of the temporal delivery of consumption volatility.