Finance and Economics Discussion Series (FEDS)
February 2007
Rational Seasonality
Abstract:
Seasonal adjustment usually relies on statistical models of seasonality that treat seasonal fluctuations as noise corrupting the `true' data. But seasonality in economic series often stems from economic behavior such as Christmas-time spending. Such economic seasonality invalidates the separability assumptions that justify the construction of aggregate economic indexes. To solve this problem, Diewert (1980, 1983, 1998, 1999) incorporates seasonal behavior into aggregation theory. Using duality theory, I extend these results to a larger class of decision problems. I also relax Diewert's assumption of homotheticity. I provide support for Diewert's preferred seasonally-adjusted economic index using weak separability assumptions that are shown to be sufficient.
Full Paper (Screen Reader Version)Keywords: Seasonality, index, numbers, separability, aggregation, duality theory
PDF: Full Paper
Disclaimer: The economic research that is linked from this page represents the views of the authors and does not indicate concurrence either by other members of the Board's staff or by the Board of Governors. The economic research and their conclusions are often preliminary and are circulated to stimulate discussion and critical comment. The Board values having a staff that conducts research on a wide range of economic topics and that explores a diverse array of perspectives on those topics. The resulting conversations in academia, the economic policy community, and the broader public are important to sharpening our collective thinking.