Application of some advances in econometrics (in the theory of cointegrated vector autoregressive models) enables us to deal effectively with two problems in rational-expectations, present-valu e models: nonstationarity of time series and incomplete data on infor mation of market participants. With U.S. data, the authors find some relatively encouraging new results for the rational-expectations theo ry of the term structure and some puzzling results for the present-va lue model of stock prices.