bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Framework for Research in Computer-Based Management Information Systems
Authors: Ives Blake , Hamilton Scott , Davis Gordon B. 
Published: November 2008

The paper presents a comprehensive framework for research in Management Information Systems (MIS). The necessity for a more comprehensive research framework is derived from a review of past research frameworks. The new framework is validated by mapping 331 MIS doctoral dissertations into its research categories. The dissertations are also classified by research methodology employed. The comprehensive MIS research model is useful not only in understanding and classifying MIS research but also in generating potential hypotheses for future research. Hypothesis generation using the model is explained and illustrated.
Profit Maximizing Perceptual Positions: An Integrated Theory for the Selection of Product Features and Price
Authors: Hauser John R. , Simmie Patricia 
Published: November 2008

An important component of marketing strategy is to “position” a product in perceptual space. But to realize a perceptual position we must model the link from physical characteristics to perceptual dimensions and we must use this model to maximize profit. This paper integrates psychological theories on how consumers process information with economic models and psychometric measurement, and it develops a theory for selecting physical features and price to achieve a profit maximizing perceptual position. The theory begins with a Lancaster-like transformation from goods space to characteristics space and investigates the implications of a mapping to a third space, perceptual space. We show that all products efficient in perceptual space must be efficient in characteristics space but not conversely. But consumers vary in their preference and the way they perceive products. Thus we introduce distributional components to the theory and derive both geometric and analytic methods to incorporate this consumer heterogeneity. Next, we investigate costs and derive a perceptual expansion path along which a profit maximizing position must exist. Conjoint analysis and quantal choice models provide the measurements to implement the theory. The theory is illustrated with a hypothetical example from the analgesics market and some of the potential psychometric measurements are illustrated with an empirical application in the communications market.
Multiple Unit Dispatches in Emergency Services: Models to Estimate System Performance
Authors: Chelst Kenneth R. , Barlach Ziv 
Published: November 2008

One emergency service system model that has undergone extensive development and testing is the hypercube queuing model and its approximate analog, which were developed by Larson. The model estimates key system performance measures, such as individual unit workloads and travel times. One limitation of this model, as well as other probabilistic deployment models, is that they assume only a single unit is dispatched to each call. In the police environment, if two officers are assigned to each unit, this assumption is generally valid. However, most fire services dispatch multiple vehicles to a serious fire, and in police departments with one-officer units, a second unit will be sent to all potentially dangerous calls. The need for a new model goes beyond an interest in more accurately estimating standard performance measures when multiple units are dispatched. New models are required to predict new performance measures that are relevant only when multiple units are dispatched. For example, what are the paired travel times of the first- and second-arriving units at an emergency? How long will the first unit be exposed at a potentially dangerous situation until a backup unit arrives? Which unit most frequently arrives first at calls requiring multiple units? In this paper we build on Larson's work and present two models, one exact, the other, approximate, which can capture the simultaneous response of two identical units dispatched to a single call. We present an example from the police context to illustrate both models and compare the speed and accuracy of the approximate model to the exact one. The workload and travel time estimates of both models differ on the average by only two percent. We conclude our presentation with a brief discussion of model extensions with a focus on the analysis of a merger of police, fire and emergency medical services into a public safety service.
Minimizing Variation of Flow Time in Single Machine Systems
Authors: Kanet John J. 
Published: November 2008

This paper addresses the problem of n jobs to be scheduled on a single machine in such a way that flow time variation is minimized. When the measure of variation is total absolute difference of completion times (TADC) the problem is shown to be quite simple. Sufficient conditions are shown for minimal TADC and a simple method for generating an optimal solution is provided. When the measure of variation is variance of flow time the problem is much more difficult. For this case a heuristic method for scheduling is proposed. The heuristic is simple and provides solutions which compare favorably with others found in the literature.
Portfolio Optimization Models for Property-Liability Insurance Companies: An Analysis and Some Extensions
Authors: Cummins J. David , Nye David J. 
Published: November 2008

This paper presents a model to assist property-liability insurance companies in making product and investment mix decisions. A quadratic programming approach is used to generate mean-variance efficient frontiers that reflect the covariability of returns on insurance lines and assets. The solution indicates the overall premium-to-surplus ratio, the distribution of premiums among insurance lines, and the proportion of assets in each major investment class that are consistent with the minimum level of risk for a given expected rate of return on net worth. Recognition is given to the tendency for some insurance lines to generate more investable funds than others due to longer lags between claim occurrence and settlement. The importance of federal income taxes in insurance company decision making is recognized, and a method is suggested for including taxes in the model. The traditional model for selecting insurance company operating strategies is safety-first decision making (ruin theory). More recently, utility theory has been suggested as an alternative approach. This paper discusses the linkages between ruin theory and utility theory and indicates how these decision rules can be used to select operating points along the efficient frontier. A numerical example is given based on the published financial data of a major insurance company to illustrate the development of an efficient frontier and the use of ruin and utility-based decision rules. The results indicate that these decision rules generally lead to different operating strategies and that efficiency can be improved using the quadratic programming approach.
Disaggregation and Resource Allocation Using Convex Knapsack Problems with Bounded Variables
Authors: Bitran Gabriel R. , Hax Arnoldo C. 
Published: November 2008

The allocation of a specific amount of a given resource among competitive alternatives can often be modelled as a knapsack problem. This model formulation is extremely efficient because it allows convex cost representation with bounded variables to be solved without great computational efforts. Practical applications of this problem abound in the fields of operations management, finance, manpower planning, marketing, etc. In particular, knapsack problems emerge in hierarchical planning systems when a first level of decisions need to be further allocated among specific activities which have been previously treated in an aggregate way. In this paper we provide a recursive procedure to solve such problems. The method differs from classical optimization algorithms of convex programming in that it determines at each iteration the optimal value of at least one variable. Applications and computational results are presented.
Note—On the Aggregation of Individual Probability Estimates
Authors: Bordley Robert F. , Wolff Ronald W. 
Published: November 2008

This Note considers the problem of aggregating individual probability estimates of an event to obtain a group estimate. Norman Dalkey has argued that no rigorous theory of probability aggregation is possible for the following reasons: (1) There is no consistent way of aggregating individual probability estimates (Dalkey's Impossibility Theorem). But Dalkey's Impossibility Theorem makes what we call the context-free assumption, namely that the group estimate of an event's probability is a function only of the estimates of the individuals and, in particular, is not dependent on the event in question. We argue that the context-free assumption is unreasonable and present several known aggregation methods which don't make it. (2) Although there is a Bayesian approach to the problem, it requires that the estimates of all but at most one of the experts be independent of the event in question. To make this argument, Dalkey assumed both: a1: The individual estimates are independent random variables, and a2: Given the occurrence or nonoccurrence of the event, the individual estimates are independent random variables. This paper presents an alternate derivation of the result, abstracting from Dalkey's context. The point is that Dalkey's result is simply a consequence of assuming both a1 and a2. It is unreasonable to assume both a1 and a2. And hence Dalkey's result does not discredit the Bayesian approach. Thus this paper resolves some theoretical objections to the possibility of a rigorous theory of aggregation. Furthermore, it clarifies the nature of the context-free assumption and the independence assumptions: a1 and a2.
Network Models for Building Evacuation
Authors: Chalmet L. G. , Francis R. L. , Saunders P. B. 
Published: November 2008

How can a large building with many occupants be evacuated in minimum time, and where are bottlenecks likely to occur in such an evacuation? In order to address this question we have constructed a family of three network building evacuation models. The most general model of interest, called the dynamic model, represents the evacuation of a building as it evolves over time, where time is represented discretely by consecutive time periods. The dynamic model triply optimizes in the sense that while directly minimizing the average over the occupants of the number of periods each needs to exit the building, it simultaneously maximizes the total number of people evacuating the building during periods 1 through p for all values of p, and also minimizes the time period in which the last evacuee exits the building. Coincident with the triple optimization, each arc dual variable indicates whether or not the building component the arc represents is a bottleneck in any period during the evacuation. The other two models in the family, referred to as the graphical model and the intermediate model, are smaller in scope than the dynamic model (they treat time as a parameter and are not time-dependent) but are easier to use, and offer alternative approaches which can provide some of the same insights as the dynamic model. We model the evacuation of an actual eleven floor building with 323 people, four elevators, and two stairwells, and compare model results with results of an observed building evacuation. We believe our models provide useful new tools for the analysis of building evacuability, and have the potential to facilitate the study of the interrelationships with building design, building redesign, and building evacuability.
Resource-Constrained Project Scheduling with Time-Resource Tradeoffs: The Nonpreemptive Case
Authors: Talbot F. Brian 
Published: November 2008

This paper introduces methods for formulating and solving a general class of nonpreemptive resource-constrained project scheduling problems in which the duration of each job is a function of the resources committed to it. The approach is broad enough to permit the evaluation of numerous time or resource-based objective functions, while simultaneously taking into account a variety of constraint types. Typical of the objective functions permitted are minimize project duration, minimize project cost given performance payments and penalties, and minimize the consumption of a critical resource. Resources which may be considered include those which are limited on a period-to-period basis such as skilled labor, as well as those such as money, which are consumed and constrained over the life of the project. At the planning stage the user of this approach is permitted to identify several alternative ways, or modes, of accomplishing each job in the project. Each mode may have a different duration, reflecting the magnitude and mix of the resources allocated to it. At the scheduling phase, the procedure derives a solution which specifies how each job should be performed, that is, which mode should be selected, and when each mode should be scheduled. In order to make the presentation concrete, this paper focuses on two problems: given multiple resource restrictions, minimize project completion time, and minimize project cost. The latter problem is also known as the resource-constrained time-cost tradeoff problem. Computational results indicate that the procedures provide cost-effective optimal solutions for small problems and good heuristic solutions for larger problems. The programmed solution algorithms are relatively simple and require only modest computing facilities, which permits them to be potentially useful scheduling tools for organizations having small computer systems.
Parametric Mixed Integer Programming: An Application to Solid Waste Management
Authors: Jenkins Larry 
Published: November 2008

A method is developed for carrying out parametric analysis on a mixed integer linear program (MILP) as either objective function coefficients or right-hand-side values of the constraints are varied continuously. The method involves solving MILPs at point values of the parameters of variation and joining the results by LP parametric analysis. The procedure for parametric analysis on the objective function can be continued until a theoretical result proves that the analysis is complete. However, a heuristic rule that is presented may greatly reduce the number of individual MILPs that have to be solved and thus reduce the total computational effort. The rule assumes that if the same values of the integer variables are optimal at two different values of the change parameter, these same integer variable values will also be optimal at all intermediate parameter values. If the rule is applied, a complete parametric analysis requires solving 2n different MILPs, where n is the number of different sets of optimal integer variable values found. We determine the savings in number of MILPs solved using the heuristic rule compared to continuing the procedure to obtain theoretical proof of completeness. The paper also proposes various possible “advanced start” aids for solving the individual MILPs. Previously there has existed no method that could be used to perform continuous right-hand-side parametric analysis on an MILP of realistic size. A heuristic rule presented here makes possible such an analysis. The procedure again requires solving 2n different MILPs. The procedures for both objective function and right-hand-side analysis can be implemented using any software that can solve MILPs and perform LP parametric analysis. Computational results are reported using commercially available packages. The procedures are applied to a large fixed-charge model that was developed to analyze where to locate resource recovery plants in Southeastern Ontario. In that model it was essential to consider very wide variation in values of the parameters related to resource recovery. It was found that the results of the parametric analyses could be distilled into clear recommendations regarding which plants to build if a resource recovery policy is implemented.
Aggregate Safety Stock Levels and Component Part Commonality
Authors: Collier David A. 
Published: November 2008

The relationship between aggregate safety stock inventory levels and component part commonality is developed. A simulation experiment strongly supports the functional form of this relationship in an uncertain operating environment. Managers can use these equations to assess the trade-offs between aggregate safety stock levels, service level and the degree of component part standardization. For example, these relationships can be used to predict service, inventory level and cost standards for any change in component part commonality.
Policy as Argument—A Logic for Ill-Structured Decision Problems
Authors: Mitroff Ian I. , Mason Richard O. , Barabba Vincent P. 
Published: November 2008

This paper presents a new framework for handling ill-structured decision problems. The framework derives from recent developments in the logic of argumentation. It shows how policy statements may under certain conditions be construed as the outcome of a complex process of argumentation. The framework is especially suited to ill-structured decision problems since it is capable of handling explicit contradictions and missing parts in an argument structure. It is also shown by means of a new concept—plausibility—how it is possible to locate the weakest links in a complex argument. A major consequence of the concept of plausibility is that it is possible under certain conditions to transform a problem in the logic of argumentation (i.e., symbolic logic) into one of algebra (i.e., linear programming).
An Experimental Comparison of Different Approaches to Determining Weights in Additive Utility Models
Authors: Schoemaker Paul J. H. , Waid C. Carter 
Published: November 2008

Several studies this past decade have examined differences between holistic and decomposed approaches to determining weights in additive utility models. Some have argued that it matters little which procedure is used, whereas others strongly favored particular methods. In this paper we address this controversy experimentally by comparing five conceptually different approaches in terms of their weights and predictive ability. The five methods are (1) multiple linear and non-linear regression analyses of ten and fifteen holistic assessments, (2) direct decomposed tradeoffs as proposed by Keeney and Raiffa (Keeney, R. L., H. Raiffa. 1977. Decisions with Multiple Objectives. Wiley, New York.), (3) a recent eigen-vector technique of Saaty (Saaty, T. L. 1977. A scaling method for priorities in hierarchical structures. J. Math. Psych. 15 (3) 234–281.) involving redundant pairwise comparisons of attributes, (4) a straightforward allocation of hundred importance points, and (5) unit weighting (i.e., equal weighting after standardizing the attributes). The decision task involved college admissions. Subjects were asked to evaluate hypothetical college applicants on the basis of verbal SAT, quantitative SAT, high-school grade point average, and a measure of extra-curricular activity. Linear as well as nonlinear attribute utility functions were used in constructing the additive models. The nonlinear functions were specified graphically by the subjects through selection from five different shapes (i.e., one per attribute). To test the predictive ability of the various models, each subject made twenty separate pairwise comparisons of alternatives (including direction and strength of preference). The prediction criteria were percentage correct predictions as well as correlations (using these twenty pairs). Seventy subjects were tested, using an (order-controlled) within-subject design, in comparing the different methods of weight determination. Monetary incentives were used to enhance motivation. In terms of findings, the methods generally differed systematically concerning the weights given to the various attributes, as well as the variances of the resulting predictions. On average, however, the methods predicted about equally well, except for unit weighting which was clearly inferior. The findings differ in this regard from the general literature. Furthermore, nonlinear models were found to be inferior to linear ones. Finally, subjects judged the methods to differ significantly in difficulty and trustworthiness, which were found to correlate inversely. The overall results raise various applied and theoretical issues, which are discussed.
An Algorithm for the Initial Dispatch of Fire Companies
Authors: Ignall E. , Carter G. , Rider K. 
Published: November 2008

In response to an incoming fire alarm, someone must decide how many and which engine and ladder companies (firefighters and their apparatus) to dispatch to the scene. Traditional dispatching policies assume that all of the designated companies are available at the time the alarm is received. These policies do not consider the workload imposed on firefighters, and do not work well at the high alarm rates now characteristic of parts of large cities. Our procedure, designed for use in New York City's computed-aided Management Information and Control System, makes good initial dispatch decisions at all alarm rates. It uses response times to serious fires to measure performance and recognizes that the dispatcher has incomplete information about the seriousness of the incident when the decision is made. A simulation comparison of our procedure with the traditional policy was made using actual incidents from July 1972. Our procedure reduced the average second engine and second ladder response times to serious fires by 25 to 45 seconds, while keeping total workload essentially unchanged. This reduction, which is about 10–15% of the five and a half minutes obtained for the traditional policy, results primarily from our procedure's deciding how many to send based on historical information on the chance that an alarm from a given location at a given time of day is serious. For example, the fraction of fires in occupied structures getting an initial second engine rose from 65% with the traditional policy to 85% with our procedure, although both policies sent an initial second engine to the same fraction of all incidents. Our procedure also reduced the number of relocations of engine companies and ladder companies substantially. The approach we used should be valuable in the design of computer-aided dispatching systems in other cities. In particular, others may find it helpful to review the way in which the objective function is developed, the way particular aspects of the dispatch problem are treated, the provision of several parameters for tuning behavior, and features of the simulation testing.
Spacecraft for Multi-Floor Layout Planning
Authors: Johnson Roger V. 
Published: November 2008

A descriptive problem definition and a tested computerized heuristic solution procedure are offered for the problem of relative location of facilities in (or layout of) a multi-floor building. The problem definition and solution procedure overcome the problem of severe nonlinearity of inter-department movement times relative to distance, which enter the multi-floor problem because of the indirectness of routing, and because of different movement speeds compared with the single floor case. Both the definition and solution procedure are application-oriented, concentrating on practical aspects of multi-floor space allocation. Substantial savings in an implementation are reported. The procedure is particularly relevant to planning for an organization moving into a new multi-floor building. Additionally, the procedure can be used, without modification, for an organization spread over more than one building, and for single floor facilities. The possibility of alternative inter-floor routings is incorporated.