A technique is presented for deriving equilibrium models of asset risk premia in continuous time models which does not require the complete solution of a consumer's continuous time stochastic control problem. The technique is used to show that even if traders have heterogeneous information about asset returns and/or there are non-traded assets, then the risk premium of a traded asset is determined by the covariance between the asset's return and the rate of change in per capita consumption. We only require the assumption that traders' consumptions and traded asset values form an Ito process.

Arguments for creating a market to allow trading the portfolio of all endowments in the entire world, the “market portfolio”, are considered. This world share market would represent a radical innovation, since at the present time only a small fraction of world endowments are traded. Using a stochastic endowment economy where preference are mean variance, it is shown that creating such a market may be justified in terms of its contribution to social welfare. It is also argued that creating a market for world shares is attractive for certain reasons of robustness and simplicity.

Arguments for creating a market to allow trading the portfolio of all endowments in the entire world, the "market portfolio," are considered. This world share market would represent a radical innovation, since at the present time only a small fraction of world endowments are traded. Using a stochastic endowment economy where preferences are mean variance, it is shown that creating such a market may be justified in terms of its contribution to social welfare. It is also argued that creating a market for world shares is attractive for certain reasons of robustness and simplicity.

[A dividend-ratio model is introduced here that makes the log of the dividend-price ratio on a stock linear in optimally forecast future one-period real discount rates and future one-period growth rates of real dividends. If ex post discount rates are observable, this model can be tested by using vector autoregressive methods. Four versions of the linearized model, differing in the measure of discount rates, are tested for U.S. time series 1871-1986 and 1926-1986: a version that imposes constant real discount rates, and versions that measure discount rates from real interest rate data, aggregate real consumption data, and return variance data. The results yield a metric to judge the relative importance of real dividend growth, measured real discount rates, and unexplained factors in determining the dividend-price ratio.]

A linearization of a rational expectations present value model for corporate stock prices produces a simple relation between the log dividend-price ratio and mathematical expectations of future log real dividend changes and future real discount rates. This relation can be tested using vector autoregressive methods. Three versions of the linearized model, differing in the measure of discount rates, are tested for U. S. time series 1871-1986: versions using real interest rate data, aggregate real consumption data, and return variance data. The results yield a metric to judge the relative importance of real dividend growth, measured real discount rates and unexplained factors in determining the dividend-price ratio.

We repeat a survey we did in the waning days of the Soviet Union (Shiller, Boycko and Korobov, AER 1991) comparing attitudes towards free markets between Moscow and New York. Additional survey questions, from Gibson Duch and Tedin (J. Politics 1992) are added to compare attitudes towards democracy. Two comparisons are made: between countries, and through time, to explore the existence of international differences in allegiance to democratic free-market institutions, and the stability of these differences.

While leading figures in the early history of economics conceived of it as inseparable from philosophy and other humanities, there has been movement, especially in recent decades, towards its becoming an essentially technical field with narrowly specialized areas of inquiry. Certainly, specialization has allowed for great progress in economic science. However, recent events surrounding the financial crisis support the arguments of some that economics needs to develop forums for interdisciplinary interaction and to aspire to broader vision.

A method is constructed for decomposing the variance of changes in incomes in the world into components, to indicate the most important risk-sharing opportunities among people of the world. A constant absolute risk premium (CARP) model, an intertemporal general-equilibrium model of the world, is presented to permit optimal contract design. For a contract designer maximizing a social welfare function, the optimal contracts maximize the equilibrium world real interest rate. Securities are defined in terms of eigenvectors of a transformed variance matrix. The method is applied using Penn World Table data on the G-7 countries, 1950–1992.

The information contained in one model's forecast compared to that in another can be assessed from a regression of actual values on predicted values from the two models. We do this for forecasts of real GNP growth rates for different pairs of models. The models include a structural model (the Fair (1976) model), various versions of the vector autoregressive (VAR) model, and various versions of a model we call the "autoregressive components" (AC) model. Our procedure requires that forecasts make no use of future information, and we have been careful to try to insure this, including using the version of the Fair model that existed in 1976, the beginning of our test period.

The market for single-family homes does not appear to be efficient. Year-to-year changes in prices tend to be followed by changes in the same direction in the subsequent year. Moreover, information about real interest rates does not appear to be incorporated in prices. There is thus a profitable trading rule for persons who are free to time the purchase of their homes. Still, overall, individual housing price changes are not very forecastable.