This paper establishes (i) an extension of Michel's (1990, Theorem 1) necessity result to an abstract reduced-form model, (ii) a generalization of the results of Weitzman (1973) and Ekeland and Scheinkman (1986), and (iii) a new result that is useful particularly in the case of homogeneous...

This paper shows stochastic versions of (i) Michel's (1990, Econometrica 58, 705--723, Theorem 1) necessity result , (ii) a generalization of the TVC results of Weitzman (1973, Manage. Sci. 19, 783--789) and Ekeland and Scheinkman (1986, Math. Oper. Res. 11, 216--229), and (iii) Kamihigashi's...