TY  - JOUR
AU  - Diba,Behzad T.
AU  - Grossman,Herschel I.
TI  - Rational Asset Price Bubbles
JF  - National Bureau of Economic Research Working Paper Series
VL  - No. 1059
PY  - 1983
Y2  - 1983
UR  - http://www.nber.org/papers/w1059
L1  - http://www.nber.org/papers/w1059.pdf
N1  - Author contact info:
Behzad Diba
Department of Economics
Georgetown University
Washington, DC  20057
Tel: 202-687-5682
Fax: 202-687-6102
E-Mail: dibab@georgetown.edu

Herschel Grossman
Department of Economics
Box B
Brown University
Providence, RI  02912
Tel: 401/863-2606
Fax: 401/863-1970
AB  - The solution to a linear model in which supply and/or demand depends on rational expectations of future prices can involve three parts, which we denote as the fundamental component, the deterministic bubble component, and the stochastic bubble component. This paper explores the properties of these solution components, emphasizing the distinction between deterministic bubbles and stochastic bubbles, for a model of inflation and for a model of the evolution of price and quantity in the market fora storable commodity, such as gold. The analysis focuses on stochastic bubbles as a possibility peculiarly associated with models that involve rational expectations. In both the inflation model and the gold model, although the analysis points to no compelling reason to rule out rational stochastic bubbles apriori, conventional behavioral assumptions imply that anyrational bubbles that arise, whether deterministic or stochastic,are explosive. The paper discusses problems of implementing econometric tests for the existence of rational bubbles, and, as an alternative to these tests, suggests "diagnostic checking" of the stationarity properties of time series. Although these diagnostic checks do not constitute definitive hypothesis testing, we conjecture they would provide strong evidence against rational bubbles outside the context of hyperinflation.
ER  -