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Compound option valuation formulae give rise to the summation of a series of multinormal distribution functions. This paper presents an identity on sums of nested multinormal distributions of arbitrary dimension. We show that this identity generalizes some well-known low order identities for the multinormal distribution. We present three applications of the new identity to contingent claims valuation problems. The first and second applications show that by reducing significantly the number of integrals to be evaluated, faster and more accurate algorithms can be developed for implementing the Geske-Johnson American put valuation formula and the Roll-Geske-Whaley American call formula; the third gives new economic insights into the valuation of disaggregated coupon bonds. [ABSTRACT FROM AUTHOR]

Expert judgment is frequently used to assess parameter values of quantitative management science models, particularly in decision-making contexts. Experts can, however, only be expected to assess observable quantities, not abstract model parameters. This means that we need a method for translating expert assessed uncertainties on model outputs into uncertainties on model parameter values. This process is called probabilistic inversion. The probability distribution on model parameters obtained in this way can be used in a variety of ways, but in particular in an uncertainty analysis or as a Bayes prior. This paper discusses computational algorithms that have proven successful in various projects and gives examples from environmental modelling and banking. Those algorithms are given a theoretical basis by adopting a minimum information approach to modelling partial information. The role of minimum information is two-fold: It enables us to resolve the problem of nonuniqueness of distributions given the information we have, and it provides numerical stability to the algorithm by guaranteeing convergence properties. [ABSTRACT FROM AUTHOR]

The paper presents a heuristic for determining the path that maximizes the expected utility of a stochastic acyclic network. The focus is on shortest route problems where a general, nonlinear utility function is used to measure outcomes. For such problems, enumerating all feasible paths is the only way to guarantee that the global optimum has been found. Alternatively, we develop a reduction algorithm based on stochastic dominance to speed up the computations. Monte Carlo simulation is used to evaluate the approach. In all, 70 test problems comprising 20 to 60 nodes are randomly generated and analyzed. The results indicate that the heuristic produces significant computational saving as the size of the network grows, and that the quality of the reduced network solutions are better than those obtained from the original formulation. [ABSTRACT FROM AUTHOR]

The Linear Programming Problem is by far the most widely used optimization model. Its impact on economic and government modeling is immense. The Simplex Method for solving the Linear Programming (LP) Problem, due to George Dantzig, has been an extremely efficient computational tool for almost four decades. The method has been the subject of intense investigations for many years, but some major aspects of its behavior are not fully understood yet. The purpose of this paper is to survey the body of knowledge on the efficiency of the Simplex Method, from both practical and theoretical points of view. Adopting the number of iterations (pivot steps) as the yardstick for efficiency, we survey four aspects of the issue: 1. Reports on practical experience of the method's performance on real-life LP problems. 2. Results on controlled (Monte-Carlo) experiments solving LP problems which were randomly generated according to some predetermined distributions. 3. Complexity results, including theoretical analyses on both upper and lower bounds for the performance of the Simplex as well as non-Simplex algorithms for LP. 4. Results of recent theoretical studies using probabilistic analysis to derive bounds on the average behavior of the Simplex Method. We discuss the consequences and limitations of the various studies. Special emphasis is given to open questions. [ABSTRACT FROM AUTHOR]

The multi-resource generalized assignment problem is encountered when a set of tasks have to be assigned to a set of agents in a way that permits assignment of multiple tasks to an agent subject to the availability of a set of multiple resources consumed by that agent. This problem differs from the generalized assignment problem in that an agent consumes not just one but a variety of resources in performing the tasks assigned to him. This paper develops effective solution procedures for the multi-resource generalized assignment problem. Various relaxations of the problem are studied and theoretical relations among these relaxations are pointed out. Rules for reducing problem size are discussed and are shown to be effective through computational experiments. Heuristic solution procedures and an efficient branch and bound procedure are developed. Results of computational experiments testing these procedures are reported. [ABSTRACT FROM AUTHOR]

Wilson (1986) gives a backwards induction algorithm for sequentially obtaining the optimal next move in a repeated Bayesian game. In this paper we show how to identify the form of an optimal solution of such a game by a graphical procedure. By means of the Prisoner's Dilemma game, we illustrate how Wilson's algorithm can be enhanced using the derived analytic form of the solution to produce an explicit optimal strategy. We can then determine not only how P[sub 1] should play on all subsequent moves of the game, but also use ideas of Bayes rationality to discuss whether a given model of P[sub 2]'s reactions is realistic. [ABSTRACT FROM AUTHOR]

Decision-making processes usually involve time-consuming and costly operations of observation and communication of the state of the environment and generation and implementation of appropriate actions. Collectively these activities may be called computational and the procedure required to carry them out may be called an algorithm. If the environment is changing stochastically the fixed computational delay involved in operating the algorithm yields obsolete actions resulting in reduced expected return. The loss as a function of delay is a measure of efficiency of the algorithm which depends upon the stochastic properties of the environment. If it is possible to reduce the loss by employing a faster algorithm at a higher cost, the algorithm may be optimally designed and selected from a given family. [ABSTRACT FROM AUTHOR]

Motivated by a planning horizon result for continuous time Markov decision chains, we study decision rules, called preferred, which may be used in the initially stationary part of nearly optimal policies. We characterize these rules and then, under conditions involving state recurrence and accessibility, consider finding such rules. We also discuss the connection between preferred rules and certain discounted process decision rules, and the role of preferred rules in optimal policies. [ABSTRACT FROM AUTHOR]

A stochastic game is played in a sequence of steps; at each step the play is said to be in some state i, chosen from a finite collection of states. If the play is in state i, the first player chooses move k and the second player chooses move l, then the first player receives a reward aikl, and, with probability pijkl, the next state is j. The concept of stochastic games was introduced by Shapley with the proviso that, with probability 1, play terminates. The authors consider the case when play never terminates, and show properties of such games and offer a convergent algorithm for their solution. In the special case when one of the players is a dummy, the nonterminating stochastic game reduces to a Markovian decision process, and the present work can be regarded as the extension to a game theoretic context of known results on Markovian decision processes. [ABSTRACT FROM AUTHOR]