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In this paper, five alternative advertising policies that belong to the advertising pulsation class are compared analytically for linear and concave response functions using a modified version of the Vidale-Wolfe model. The results of the research show that (1) For both linear and concave response functions, advertising pulsing/maintenance policy dominates advertising pulsing policy but is dominated by the Uniform Advertising Policy. For convex response functions, the order of dominance is reversed. (2) For linear response functions, uniform advertising policy dominates the impulse advertising policy but is dominated by the chattering advertising policy. (3) For concave response functions, uniform advertising policy dominates both the impulse advertising policy and the chattering advertising policy. (4) For convex response functions, chattering advertising policy dominates both the advertising pulsing policy and the impulse advertising policy. The Vidal-Wolfe model is estimated using the well-known Lydia Pink data. Optimality analysis shows that the company was over advertising about half of the time studied. Over advertising seems to have produced appreciable gain in sales and created significant harriers to competitive entry at a little cost in terms of foregone profits. [ABSTRACT FROM AUTHOR]

This paper presents a practical method for determining the waiting time distribution of a single-stage queueing system for general distribution of inter-arrival/ service times. The method requires the matrix solution of Lindley's equation for waiting time distribution by treating time in discrete units. Some important characteristics of the method are: a) it is easily programmable; b) it has high accuracy; c) it has modest CPU time and storage requirements; and, d) it requires no mathematical functional form for inter-arrival/service time distributions. [ABSTRACT FROM AUTHOR]

This paper discusses the Stochastic Dominance (SD) approach to the evaluation of risky assets. Given a set of portfolios, the familiar EV procedure chooses a set of EV-efficient portfolios while the SD procedures choose SD-efficient sets that usually are quite similar to (but not identical with) the EV-efficient set. The SD approach can be employed as a refinement of the EV model or as an alternative method of evaluating portfolios. The SD view has certain conceptual advantages in the screening of a set of portfolios, but the EV model has the important advantage of an optimizing algorithm that builds efficient portfolios. Also, the SD approach requires more data than the EV approach. [ABSTRACT FROM AUTHOR]

This paper attempts to isolate and analyze the principal ideas of multiobjective optimization. We do this without casting aspersions on single-objective optimization or championing any one multiobjective technique. We examine each fundamental idea for strengths and weaknesses and subject two—efficiency and utility—to extended consideration. Some general recommendations are made in light of this analysis. Besides the simple advice to retain single-objective optimization as a possible approach, we suggest that three broad classes of multiobjective techniques are very promising in terms of reliably, and believably, achieving a most preferred solution. These are: (1) partial generation of the efficient set, a rubric we use to unify a wide spectrum of both interactive and analytic methods; (2) explicit utility maximization, a much-overlooked approach combining multiattribute decision theory and mathematical programming; and (3) interactive implicit utility maximization, the popular class of methods introduced by Geoffrion, Dyer, and Feinberg and extended significantly by others. [ABSTRACT FROM AUTHOR]

In the context of deterministic multicriteria maximization, a Pareto optimal, nondominated, or efficient solution is a feasible solution for which an increase in value of any one criterion can only be achieved at the expense of a decrease in value of at least one other criterion. Without restrictions of convexity or continuity, it is shown that a solution is efficient if and only if it solves an optimization problem that bounds the various criteria values from below and maximizes a strictly increasing function of these several criteria values. Also included are discussions of previous work concerned with generating or characterizing the set of efficient solutions, and of the interactive approach for resolving multicriteria optimization problems. The final section argues that the paper's main result should not actually be used to generate the set of efficient solutions, relates this result to Simon's theory of satisficing, and then indicates why and how it can be used as the basis for interactive procedures with desirable characteristics. [ABSTRACT FROM AUTHOR]

The entropy measure H = - Σpi log pi is being used with increasing frequency in the analysis of business and economic data. It is, however, simply another measure of dispersion which can be related to the moments of the probability function. Its virtues stem from its decomposition and interpretative properties. This paper surveys the uses to which the measure has been put in the literature, and discusses whether its use has been appropriate and innovative. [ABSTRACT FROM AUTHOR]

This paper investigates portfolio revision with an emphasis on the decision of when to revise. A statistical technique based on the sequential analysis of the time series of portfolio return relatives determines when revision is to occur. The technique detects changes in the time series which are an indication that the underlying generating process of the time series has changed and that the portfolio should be, if necessary, revised. Thus, the length of the revision interval is variable and a function of the data. The statistical technique is utilized in conjunction with three portfolio revision strategies. These three revision strategies are compared to a buy and hold policy over three nonoverlapping, 12-year investment horizons. The basis of comparison is the net terminal values which include adjustments for transaction costs and taxes. The sensitivity of the statistical technique to its parameters is also analyzed. [ABSTRACT FROM AUTHOR]

This paper gives a survey of piecewise approximation functions. Aside from the use of dummy variables, little research has employed such functions. Piecewise functions permit the dependent variable of a functional relationship to take on different forms with respect to the independent variable on various subintervals of the domain of the independent variable. Three types of piecewise approximation functions are considered: dummy variables, piecewise linear regressions and cubic splines. The theoretical and empirical properties of such functions are discussed within the context of an illustrative example involving the increase in ridership over time on urban mass transit systems. Dummy variables take account of shifts in the structural relation in a discontinuous fashion. Piecewise regressions and cubic splines allow for structural shifts without discontinuities arising. Tests are performed to determine whether a linear, quadratic, or cubic piecewise continuous function should be employed. In addition a test is employed to see if structural change occurs in the functional relation at the shift points. [ABSTRACT FROM AUTHOR]

The expected geometric mean has been shown to be a valuable criterion in ranking portfolios of assets. For example, under certain conditions the maximum expected geometric-mean portfolio minimizes the expected time to amass a fixed level of wealth as wealth becomes "large." This paper develops a simple algorithm for obtaining such portfolios when portfolio returns are assumed to be lognormally distributed. The risk-return characteristics of portfolios are derived and illustrated using data from a subset of stocks found on the New York Stock Exchange. [ABSTRACT FROM AUTHOR]

The paper presents an analytical description of a state-dependent assignment policy, where different assignments of attributes to objects are employed under different states. Various considerations, other than optimizing an objective function, present themselves for such cases—for example, the existence of groups of assignees with certain levels of intragroup assignment uniformity, the stability of the policy over states, the presence of a revealed preference ordering of the assignments, and others. An approach towards a quantitative treatment of such features of a state-dependent assignment policy is discussed, and in particular a uniformity measure is defined and its properties are investigated. Potential uses of the model are suggested for urban emergency services, questionnaire analysis, task allocation, medical diagnosis, and dynamic computer program behavior. Three implementations for questionnaire analysis are reported. [ABSTRACT FROM AUTHOR]

A major difficulty in practicing constrained nonlinear optimization is that different optimization algorithms are effective for different classes of problems. The search algorithms tested were selected because they seemingly had the capability of solving ill-defined problems. The emphasis of this research was on problems that are realistic and do not necessarily satisfy the classical assumptions of convexity, continuity, unimodality, etc. All algorithms were tested on a variety of problems. A problem was described by three types of attributes: the environmental attributes, the objective function attributes, and the constraint set attributes. The results of the study provide selective logic for choosing an effective search algorithm. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the effects of different interdisciplinary problem-oriented formats on a student's knowledge of and retention of disciplinary concepts and principles, his application of these concepts and principles to disciplinary problems, and his use of a discipline in his analysis of a complex problem. Performances of students enrolled in the experimental sections were compared to those of students enrolled in standard lecture-discussion sections. Regression analysis was used to analyze students' performance in order to control the effects of differences in student backgrounds. It was found that altering the pedagogical format and reward system within the experimental sections had no significant effect upon student performances in the experimental, problem-oriented program. In general, this study indicates that students taught in the standard lecture-discussion format in which grades are determined by examination over course material retain concepts and principles, apply these concepts and principles to disciplinary problems, and integrate disciplinary concepts into their analysis of complex problems as well as, if not better than, students taught in an interdisciplinary, problem-solving format. [ABSTRACT FROM AUTHOR]

The quantitative disciplines have focused their efforts primarily upon more complete and efficient methods for analyzing decision problems. Almost totally neglected in these efforts is the interplay between a decision technique and its ultimate user. This interface is of crucial importance to the continued success of the decision sciences in organizations. Data are presented to support the contention that decision techniques and their resultant impact on job content interact with psychological variables to cause variation in user satisfaction and performance. These results are similar to the effects hypothesized to occur at blue collar levels in organizations. [ABSTRACT FROM AUTHOR]

Analyzes several tests of the nature of weekly yield movements and to view the results of their applications with respect to industrial bonds. Possibility of predicting future yield changes by using past yields alone, given a sequence of actual yields; Question of whether bond yields are trends or random walks.

Implications of a probabilistic random walk model of incremental sales response to advertising are develop for various timing patterns of advertising expenditures. Maximum likelihood procedures for assessing advertising effectiveness and for estimating a decay (forgetting) rate are developed and applied to artificial data of known configuration and are used to assess the impact over time of a brochure program on mail order sales. Results are also compared to those from alternative models involving various tag patterns in advertising effects. [ABSTRACT FROM AUTHOR]

The primary purpose of this note is to point out that while the test proposed in the article "A Test for the Detection of a Poisson Process" by Reinmuth published in the periodical "Decision Sciences," Vol. 2, 1971 is well-known, it is not a good procedure for this application. Secondly, this note aims to suggest more appropriate methods of analysis.