This paper analyzes a one-commodity model in which alternative investment projects are characterized by return functions indicating the output intensities over time resulting from an initial unit investment. Saving is generated partly by households as a constant fraction of net income, and partly by business firms in accordance with a depreciation (or replacement) policy. It is shown that when a declining value depreciation policy is adopted, the ordering of consumption streams in terms of their present values, at any fixed interest rate for which these converge, induces an ordering of investment projects in terms of their internal rates of return. The same ordering of projects is also induced by applying the overtaking criterion to the consumption streams.

[Under classical assumptions, characterizations are given for two classes of instrumental variable estimators of an equation in a simultaneous system. IV estimators where all instruments are nonstochastic are expressed in terms of multinormal random vectors in exactly the same way as the 2SLS estimator of a just-identified equation. These estimators have no finite moments of positive integral order. The second class, consisting of IV estimators based on certain stochastic instruments, includes the OLS, 2SLS, and modified 2SLS estimators. The inadmissibility (under squared-error loss) of some estimators in this class is considered when the equation being estimated contains two endogenous variables.]

In recent studies of the temporary competitive equilibrium, agents' current decision correspondences are derived using a standard recursion procedure, which is only applicable when the planning horizon is finite. This paper presents a general derivation of the current decision rule without restrictions on the time horizon or the number of states of the world in any period. It is shown that if utility is continuous in the product topology and if, in each period, expectations and the current constraint correspondence are continuous, then the current decision rule is upper semi-continuous. This result is obtained by associating with each current decision a set of feasible future plans. The expected utility of a current decision is then the expected utility of the best feasible future plan. The feasible future plan correspondence is shown to be continuous and the Maximum Theorem completes the proof.

In this paper, we develop a Capital Asset Pricing Model (CAPM) using a mean-lower partial moment framework. We explicitly derive formulae for the equilibrium values of risky assets that hold for arbitrary probability distributions. We show that when the probability distributions and portfolio returns are either normal, stable (with the same characteristic exponent between 1 and 2 and the same skewness parameter, not necessarily zero), or Student-t distributions, our CAPM reduces to the traditional mean-scale CAPM's. Consequently, since the traditional equilibrium models are special cases of our model, the mean-lower partial moment framework is guaranteed to do at least as well in explaining market data. As an application of our theory, we derive an acceptance criterion for capital investment projects and note that corporate finance theory results developed, for example, in the well-known mean- variance framework carry over to the mean-lower partial moment framework.

This paper develops optimal portfolio choice and market equilibrium when investors behave according to a generalized lexicographic safety-first rule. We show that the mutual fund separation property holds for the optimal portfolio choice of a risk-averse safety-first investor. We also derive an explicit valuation formula for the equilibrium value of assets. The valuation formula reduces to the well-known two-parameter capital asset pricing model (CAPM) when investors approximate the tail of the portfolio distribution using Tchebychev's inequality or when the assets have normal or stable Paretian distributions. This shows the robustness of the CAPM to safety-first investors under traditional distributional assumptions. In addition, we indicate how additional information about the portfolio distribution can be incorporated to the safety-first valuation formula to obtain alternative empirically testable models.

The work of Black and Scholes [2] and Merton [4] suggests that analysis of hedged positions in a continuous time random walk model yields powerful insights into the valuation of financial securities. The present paper extends this methodology in a straightforward fashion to foreign exchange transactions. By adopting the device of hedging in a secondary market for forward currency contracts against a long position in spot currency, a simple statement of boundary conditions for the forward position can be detailed. This allows a direct solution of the continuous time valuation problem that yields the interest rate parity theory.

The option pricing model developed by Black and Scholes and extended by Merton gives rise to partial differential equations governing the value of an option. When the underlying stock pays no dividends – and in some very restrictive cases when it does – a closed form solution to the differential equation subject to the appropriate boundary conditions, has been obtained. But, in some relevant cases such as the one in which the stock pays discrete dividends, no closed form solution has been found. This paper shows how to solve these equations by numerical methods. In addition, the optimal strategy for exercising American options is derived. A numerical illustration of the procedure is also presented.

Frederick D. S. Choi, Teaching International Finance--An Accountant's Perspective, The Journal of Financial and Quantitative Analysis, Vol. 12, No. 4, Proceedings of the 1977 Western Finance Association Meeting (Nov., 1977), pp. 609-614