bluuebunny/crossref_metadata_2025_split huggingface dataset:
Television and Efficiency in Higher Education
Authors: Jamison Dean T. , Lumsden Keith G. 
Published: November 2008

ITV has long been heralded as providing the potential for substantial improvements in the quality, or reductions in the cost, of higher education. Yet there exist no analytical models that would allow a quantitative expression of the extent to which ITV could, in fact, improve educational efficiency. Our purpose in this paper has been to develop such a model. The model is developed in terms of efficiency improvement in a 2 year professional school; it generalizes readily, however, to any institution of higher learning that has a substantial number of multi-section courses. In addition to development of a theoretical model we experimentally tested our proposed approach in an introductory microeconomics course at the Stanford University Graduate School of Business. Our results reconfirmed the well established result that substituting ITV for live instruction has insignificant impact on student learning, and our detailed analysis of student attitudes (expressed in part as willingness to pay) gives confidence that ITV (combined with small group discussion) can be an acceptable substitute for lecture instruction in higher education. Given this high degree of substitutibility, application of our quantitative model indicates substantial efficiency improvements to be possible in higher education through relatively limited use of ITV.
A Deterministic Multi-Period Production Planning Model with Piecewise Concave Production and Holding-Backorder Costs
Authors: Swoveland Cary 
Published: November 2008

A single product, finite horizon production planning model with known requirements is considered. Production and holding-backorder cost functions are assumed to be piecewise concave, thereby allowing an arbitrarily close approximation to a wide range of cost functions which one might encounter in practice. In each period production, inventories and backlogged orders may not exceed prescribed levels. Production (inventory) breakpoints are the endpoints of the intervals over which the production (holding-backorder) cost functions are concave. It is shown that there is an optimal production schedule which has the property that between successive periods in which ending inventories are at inventory breakpoint levels there is at most one period in which production is not at a production breakpoint level. This property, which is an extension of recent results obtained by Florian and Klein [Florian, Michael, Morton Klein. 1971. Deterministic production planning with concave costs and capacity constraints. Management Sci. 18 (1, September) 12–20.] and Love [Love, Steven F. 1973. Bounded production and inventory models with piecewise concave costs. Management Sci. 20 (3, November) 313–318.], suggests a straight-forward dynamic programming algorithm for obtaining an optimal solution.
A Primal-Dual Traffic Assignment Algorithm
Authors: Petersen E. R. 
Published: November 2008

A new algorithm for solving the traffic assignment problem is presented. This is a primal-dual algorithm which utilizes a flow augmentation primal and a shortest path dual procedure. At each iteration a feasible solution is known together with a measure of “goodness” of the solution. It is shown that the algorithm converges to an optimal solution. Experience with the algorithm suggests that this convergence is very rapid.
A Simulation Study of Alternative Pollution Control Enforcement Systems
Authors: Downing Paul B. , Watson William D. 
Published: November 2008

Simulation analysis is used to investigate enforcement of the new source performance standard for particulate matter discharges from coal-fired power plants. The analysis uses engineering and econometric estimates of relevant cost and performance paramenters. Results are generalized by Monte Carlo selection over distributions of each of the appropriate parameter values. The simulations are summarized through regression analysis on the outcomes. Under current legal enforcement it is found that most power plants will violate the standard, that small plants will control to higher removal levels than large plants and that power companies will install relatively costly pollution control technology. Three enforcement alternatives are considered for overcoming these shortcomings: more stringent legal enforcement, enforcement using emission taxes, and a mixed system which uses device certification tests and emission taxes. It is found that each of the alternatives can lead to the standard being met and to more-or-less equal sharing in control burden across plant size. But it is only the two systems which use emission taxes that give incentive for choosing least costly control technology. It is also suggested that emission tax systems are likely to provide stronger incentives toward early compliance. The general applicability of these conclusions to other enforcement situations is discussed.
Some Properties of a Decentralized Adjustment Process
Authors: Simonovits András 
Published: November 2008

This paper deals with some properties of a decentralized adjustment process which were investigated originally by T. A. Marschak in [Marschak, J. 1968. Computation in organizations: Comparison of price mechanisms and other adjustment processes. Risk and Uncertainty Proceedings of an International Economic Association Conference, Ch. XII. of McGuire, C. B., R. Radner (1972), eds. Borch and Mossin, St. Martin's Press, New York, 1972.]. We correct some mathematical errors. Marschak compares the gross expected payoffs of centralized and decentralized mechanisms. We prove that his Proposition 5: “the greater regular rate is the better” [Marschak, J. 1968. Computation in organizations: Comparison of price mechanisms and other adjustment processes. Risk and Uncertainty Proceedings of an International Economic Association Conference, Ch. XII. of McGuire, C. B., R. Radner (1972), eds. Borch and Mossin, St. Martin's Press, New York, 1972, p. 261] is not correct in this generality and replace it with the exact theorem on the rate-optimum. We analyse Marschak's Paradox 1 [Marschak, J. 1968. Computation in organizations: Comparison of price mechanisms and other adjustment processes. Risk and Uncertainty Proceedings of an International Economic Association Conference, Ch. XII. of McGuire, C. B., R. Radner (1972), eds. Borch and Mossin, St. Martin's Press, New York, 1972, p. 263: Proposition 6] and prove that it is not a real paradox, namely, that it would hold only if the components of a certain random variable-vector were correlated, a case treated separately. Finally Marschak's problem on the finiteness of a modified adjustment process is solved.
Stochastic Programming of Multiple Channel Service Systems with Deterministic Inflow and Stochastic Service Times
Authors: Resh Michael , Friedman Moshe 
Published: November 2008

The problem of allocating customers of different types to various channels of a service system is considered. Service times are assumed to be independent identically distributed random variables whose distribution functions depend on the type of customers as well as the service channel. The total loading time of each channel consists of the sum of service times of all customers which were allocated to it and is thus a random variable also. If the loading time of a given channel exceeds (falls short) its nominal capacity, an overtime (idle time) penalty is incurred. Penalties are assumed to be proportional to the time lapse involved. There is also a revenue gain which is proportional to the number of customers served. The objective is to find the optimal allocation of customers to channels, xij, such that the expected net gain, revenue minus losses, is maximized. It is shown that the distribution function of a loading time depends on the choice of the xij and hence that, in general, no claims can be made with respect to desirable convexity properties of the objective function. It is further shown that if the service times are assumed to be normally distributed, then the objective function depends also on the means and the variances of the loading times. The mathematical properties of the program are utilized to ascertain that the solution obtained via a suggested algorithm is global. The nonlinear program is reduced to a (possibly iterative) solution of a linear program by using previous results obtained by the first author.
An Optimal Tax Incentive Scheme for a Decentralized Multi-Product Firm
Authors: Venezia Itzhak 
Published: November 2008

Consider a multi-product firm facing an uncertain demand. It will be shown that the firm may benefit from decentralizing the decisions of how much to produce. To obtain these benefits, the firm should use the suggested internal tax incentive scheme. The quantities determined under the suggested scheme are equal to the sum of the quantities determined under centralization and a random vector with zero mean. This result is attributed to the dynamics by which a decentralized solution is obtained. It follows that the central planner may improve his decisions by behaving according to similar dynamics. A tax incentive scheme which guarantees improvement by decentralization may be unfair to some decentralized units. Sufficient conditions will be given for the existence of a fair scheme which improves on the centralized solution. It will be shown that if the uncertainty in the demand is large such a scheme will usually exist.
Lot Sizing and Sequencing for N Products on One Facility
Authors: Delporte Christian M. , Thomas L. Joseph 
Published: November 2008

The problem of determining both lot sizes and repeating sequences for N products on one facility is difficult due to the combinatorial and continuous nature of the problem. The work that has been done on the problem has made various assumptions (“zero-switch rule” or “equal lot size,” for example) to simplify the problem. Several heuristics have been suggested that come fairly close to a computable lower bound on cost. This paper discusses a mathematical programming formulation of the entire problem, along with reasons for its (current) nonpracticality. Heuristics for reducing the problem to a manageable mathematical programming formulation are presented. Specifically, a formulation is given when the sequence is known with both (potentially unequal) lot sizes and idle time periods as variables. The formulation is a convex quadratic program. Heuristics for finding sequences (to feed to the quadratic program) are explored, and examples from previous literature demonstrate that the methods here give consistent results as good as and sometimes significantly better than previous methods. Finally, we discuss situations in which such methods might be important and situations in which easier methods should suffice.
Nevada's Gaming Revenues: Time Characteristics and Forecasting
Authors: Cargill Thomas F. , Eadington William R. 
Published: November 2008

The growing interest in gaming activity has led to an increased interest in Nevada's economy. Gross gaming revenues are regarded as an important economic indicator of the Nevada economy and of considerable importance to the State's budgetary planning since taxes derived from these revenues represent almost fifty percent of the general revenues in any given year. The major objective of this study is to identify the time varying characteristics of quarterly gaming revenues over a twenty-year period for the three most important economic areas within Nevada. This will provide the basis for developing a meaningful forecasting methodology. Examination of the gaming revenues for seasonal and non-seasonal fluctuations indicate that each area's revenues exhibited a consistent seasonal pattern and the amplitude of the seasonal fluctuation tended to diminish over time. No significant evidence of non-seasonal fluctuations such as business cycles could be found. Based on the time characteristics of the gaming revenues it was concluded that the autoregressive-moving average forecasting techniques suggested by Box and Jenkins would be the most appropriate forecasting methodology to employ. A Box-Jenkins model was estimated for each area over a period ending in 1974-IV and forecasts were generated for the period from 1975-I to 1977-IV. The forecasts were judged to be reasonably close to actual gaming revenues at least for the first 6 quarters of the forecast period.
Queues with Instantaneous Feedback
Authors: D'Avignon Gilles R. , Disney Ralph L. 
Published: November 2008

Queueing problems in which a customer having received a unit of service, returns to the waiting line, under some decision rule, to receive another unit of service occur often in applications. Inspection procedures provide such a framework for units that must be reworked. A large class of such problems appears in computer modelling under the name of round-robin models and foreground-background models. In the present paper, such a system is referred to as a queue with instantaneous feedback. Throughout the text it is assumed that there are two independent Poisson arrival processes giving two types of customers. Each type of customer has its own service time distribution. The decision to feedback (to receive another unit of service) or not is based on the type of customer completing service. Conditions for the existence of a steady state queue length are found and some joint and marginal distribution of these queue lengths are given. Moreover it is shown that several earlier results in queueing and computer modelling can be obtained simply from the results given here. A particular case of the foreground-background model in computer systems analysis serves as an example.
Multi-Stage Production Planning
Authors: Gabbay Henry 
Published: November 2008

The impact of poor production and inventory planning can be significant in any manufacturing firm. On an aggregate level, excessive inventories can lead to poor cash flows necessitating financing to cover operational costs while stock outs can lead to customer service problems and the eventual loss of business. Therefore managers must utilize their aggregate resources effectively while optimizing individual item run quantities on a daily operational level. This paper presents an analytic framework for a hierarchical treatment of a multi-stage linear programming production and inventory problem. The paper is an extension of the single stage case by the author. The problem we address is multi-item, capacitated, and linear. We require certain cost assumptions: monotone costs to determine an optimal aggregate plan and to establish planning horizons, and separability of costs to optimally disaggregate aggregate production. The hierarchical procedure not only makes business and organizational sense, but is also analytically feasible, computationally attractive, and reduces detailed forecasting requirements. The intent of the paper is twofold: first to present an alternative to the classical single monolithic model for the manager and analyst and second, to provide, for the researcher, a basis for a potentially fruitful area of research in hierarchical planning.
The Optimum Span of Control in a Pure Hierarchy
Authors: Keren Michael , Levhari David 
Published: November 2008

This is a model of a pure hierarchy which oversees a given number of productive units. Its aim is to minimize costs, which are the sum of wage costs and costs caused by delays in decision making. The advantage of the model is that it permits the calculation of an optimum formal structure of the hierarchy in terms of the span of control at different levels. The general result is that spans of control should increase as one goes down the levels of the hierarchy. However, when time savings become more and wage costs less important, the difference between the optimum spans of control shrinks; in the limit, when wage costs are not considered at all, they become equal. These results support the findings of some empirical studies: there is evidence for increasing spans of control in business organizations, while in armies, where cost considerations are secondary, spans of control tend to be more uniform.
Incentives in a Divisionalized Firm
Authors: Groves Theodore , Loeb Martin 
Published: November 2008

This paper examines the problems of coordinating and controlling divisions of a large firm. Divisions are typically interdependent and the corporate headquarters plays an important role in coordinating such decisions as pricing, allocation of funds to the divisions, and determining the level of corporate-wide research and development. One important problem is how to provide division managers with incentives both to act in congruence with the goals of the overall firm and to transmit accurate information to the corporate center so that the center's decisions may be enhanced. The analysis proceeds by assuming that each division manager possess perfect knowledge of his own division's technology and the market conditions it faces. Each division's profits, however, depend upon certain coordinating decisions taken by the center. The center is assumed to be at least partially ignorant about the operations of the divisions and to rely upon information from the divisions in making coordinating decisions. A control structure for a divisionalized firm is defined to be a set of rules for evaluating division managers and a decision-rule for central coordinating decisions. Division managers are assumed to act to maximize their evaluation measures so that managerial shirking is not considered. In this setting where perfect information is available, problems of risk aversion and risk sharing do not arise, and a minimum test for optimality of a control structure is given. Specifically, when each division manager seeks to maximize his own evaluation measure and when the center uses its decision-rule for coordination, overall firm profits should be maximized. A control structure is proposed in which the center acts as if it is receiving “truthful” information from the division managers. This naive decision rule is justified by the accompanying evaluation measures that provide division managers with incentives to communicate in an honest manner. With the proposed evaluation measures, each division manager is rewarded on the basis of his division's contribution to overall profits. If the division's message to the center has no impact on the center's coordinating decisions, then the manager is evaluated on the basis of his own division's realized profits. If the division's message changes the coordinating decision, then the manager is evaluated on the basis of his division's realized profits less the reported impact of the change in coordinating decisions (resulting from his message) on the profits of the other divisions. It is shown that with this evaluation measure, a division manager is best off communicating truthfully, regardless of the messages of all others. The proposed control structure, therefore, provides an alternative to traditional profit-sharing. An application of the control structure to a resource allocation problem is also given.
Note—Computation of Particular Economic Equilibria
Authors: Bracken Jerome , Falk James E. 
Published: November 2008

The computation of economic equilibria, given specific supply and demand functions, is a well-established problem normally treated by fixed point methods or other iterative schemes which converge to a point satisfying the equilibrium criteria. In cases where there are several points which satisfy the equilibrium criteria, these methods will produce a solution distinguished only by the characteristics of the method itself and the starting point used. For some applications, it is desirable to characterize a particular equilibrium point in the presence of multiple equilibria. We consider here economies with demand and supply characteristics which can be described in terms of separable functions (i.e., functions which are sums of functions, each of a single variable) or in terms of functions which can be made separable by introducing new variables and equations. We apply a recently developed branch and bound algorithm to the problem of maximizing any one of several separable objective functions subject to the equilibrium criteria, thus producing a particular equilibrium point. If there is more than one equilibrium point solution for a particular objective function, the branch and bound procedure will produce all such solutions. We present an example with three commodities to show that economic equilibrium models can have different solutions depending on which objective function is used. We briefly discuss other examples with up to 30 commodities.
The Beta Distribution as a Model of Behavior in Consumer Goods Markets
Authors: Stewart John F. 
Published: November 2008

Loyalty in branded consumer goods markets is a subject that has often been discussed in the marketing literature. Virtually no matter what definition of loyalty has been adopted, it has been found to exist. This paper examines loyalty from a different perspective—that of an aggregation of consumers' probabilities of purchasing a particular brand, called the loyalty distribution. Loyalty in this context implies that most consumers should either have high probabilities of purchasing the brand or high probabilities of purchasing one of the competitive brands; few consumers have equally likely probabilities of purchasing the brands in a market. Another way of stating the point is that the majority of consumers are loyal and tend to repeat purchase their favorite brand while few are nonloyal and tend to switch back and forth. The Beta distribution is examined as a model of the loyalty distribution. It is demonstrated that, if this distribution is a good model for the underlying process, it is possible to define, in terms of brand share and repeat, the conditions under which the loyalty distribution will assume each of its possible shapes. Since the U or J shape is consistent with loyalty in consumer goods markets, the requirements for this shape are emphasized. It is shown, in particular, that, in order to maintain one of these shapes, a brand must have a greater percent of its share accounted for by repeat purchasing the larger its share of market. A model of switching and repeat based on the Beta is explored and a number of examples of the characteristics of the model in different markets are worked out. Maximum switching is shown to occur in markets with equal share brands, i.e., maximum entropy markets. Total switching is shown to increase at a decreasing rate as the number of brands in the market increases. Finally, a number of areas for further research are suggested. The model developed has barely scratched the surface of its potential.
Optimal Multi-Level Lot Sizing for Requirements Planning Systems
Authors: Steinberg Earle , Napier H. Albert 
Published: November 2008

The wide spread use of advanced information systems such as Material Requirements Planning (MRP) has significantly altered the practice of dependent demand inventory management. Recent research has focused on development of multi-level lot sizing heuristics for such systems. In this paper, we develop an optimal procedure for the multi-period, multi-product, multi-level lot sizing problem by modeling the system as a constrained generalized network with fixed charge arcs and side constraints. The network permits us to relax some of the more restrictive assumptions of previous models such as those designed for product structures with single sources or successors. The solution to the resulting minimum cost flow problem yields optimal lot sizing decisions for all purchases as well as manufactured goods and components in all periods over a finite planning horizon. A simple illustration, beginning with a master production schedule and bills of material, illustrates the suitablility of this approach for modeling complex requirements planning systems. Optimal solutions obtained by this method may also be useful in comparing results obtained from future heuristic approaches which may be more computationally efficient.