[Changes in asset prices are shown to produce only substitution effects in a broad class of portfolio-choice models. Wealth effects are identically zero unless the individual's stocks of assets are subject to unanticipated changes.]

[The problem under consideration is to select the smallest majority size such that at least one social state is not defeated by any other when restrictions on possible voters' preferences are explicitly known, and when populations of arbitrary size are possible. This problem is formulated in mathematical programming terms. The special structure of the formulation is discussed, and some results concerning bounds on the majority sizes are established.]

[This paper is concerned with "supergames" in which the action taken in a given time period by a player will affect the payoff to any other player in the subsequent period. A supergame consists of a set of players and a countable sequence of "ordinary" games. To illustrate "time-dependence," consider an economic market in discrete time. Say each firm must choose a price in each time period. This market has time-dependence if the amount demanded of a firm today is a function of the prices chosen today and of the prices chosen in the preceding period. Conditions are given for the existence of non-cooperative equilibria of two types: (i) steady state, in which the individual moves of the players converge over time to some s extasciicircum0 and (ii) balance temptation equilibria of the sort developed by Friedman [6] for games lacking time dependence.]

This paper reports on some mathematical and analytical properties of a static nonlinear model of a national economy or, more generally, of a multisectored economy. The model is a nonlinear version of the well-known linear input-output model of Leontief. Conditions are given for the nonlinear model to be workable in the sense that (i) there is a unique nonnegative vector of output production levels for each nonnegative final-demand vector, and (ii) the vector of output levels depends in a certain reasonable manner on the finaldemand vector. Attention is also focused on several other properties of the model of economic interest. For example, it is shown that propositions completely analogous to the LeChatelier-Samuelson principle in both the weak and strong forms for workable Leontief systems are valid within the context of the nonlinear model.