On Viable Diffusion Price Processes of the Market Portfolio
研究市场组合价格遵循扩散过程时，代表性个体效用函数的确定，并给出该过程可行的充要条件，发现可行扩散过程是一个相当受限的族。
ABSTRACT The assumption that the market portfolio follows a specified diffusion process implies, in a simple equilibrium framework, that the representative individual must have a certain utility function which is identified in the paper. Not every diffusion process is viable, i.e., can be “endogenized” to be the market portfolio's price process in such an equilibrium model. The paper provides necessary and sufficient conditions for viability which imply that viable diffusion processes constitute a rather restricted family.