bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reversibility of Tandem Blocking Queueing Systems
Authors: Yamazaki Genji , Kawashima Takeshi , Sakasegawa Hirotaka 
Published: November 2008

This paper is concerned with queueing systems of several service stations in series in which each station may consist of multi-servers. An infinite number of customers always waits in front of the first station, and each customer passes through all of the stations in sequence. There is only a finite number of waiting positions between any two adjacent stations. The service time for a customer at any station is assumed to be a random variable, the distribution of which may depend on the station. In this mode of operation the servers at any station will at any time be busy, idle, or blocked. This blocking system is said to be C-reversible if the capacity remains invariant under reversal of the system. The reversed system is obtained by reversing the original stations' order, that is, every customer in the reversed system passes through the original stations in the reverse order. It has already been proved that C-reversibility holds for any blocking system in which each station consists of either a single server of nondeterministic service times or multi-servers of deterministic service times, and that the blocking system has a stronger property than C-reversibility. In this paper we show that two-station blocking systems with multi-server stations of nondeterministic service times are C-reversible, but this property can no longer be extended to three or more station blocking systems with multi-server stations of nondeterministic service times. We also show for the case of multi-server stations of nondeterministic service times that the stronger property which involves invariance of distribution does not hold even for two-station blocking systems.
Modeling Data and Process Quality in Multi-Input, Multi-Output Information Systems
Authors: Ballou Donald P. , Pazer Harold L. 
Published: November 2008

This paper presents a general model to assess the impact of data and process quality upon the outputs of multi-user information-decision systems. The data flow/data processing quality control model is designed to address several dimensions of data quality at the collection, input, processing and output stages. Starting from a data flow diagram of the type used in structured analysis, the model yields a representation of possible errors in multiple intermediate and final outputs in terms of input and process error functions. The model generates expressions for the possible magnitudes of errors in selected outputs. This is accomplished using a recursive-type algorithm which traces systematically the propagation and alteration of various errors. These error expressions can be used to analyze the impact that alternative quality control procedures would have on the selected outputs. The paper concludes with a discussion of the tractability of the model for various types of information systems as well as an application to a representative scenario.
The Managerial Economics of Civil Litigation
Authors: Levy Ferdinand K. 
Published: November 2008

As the United States has become a more litigation society, executives are finding more of their time and their firms' resources consumed by litigation. This paper attempts to assist their decision making with regard to legal matters by looking at the following questions: Under what conditions should a potential plaintiff litigate a specific issue? Under what conditions should a defendant faced with a lawsuit respond forcefully to it? How can legal expenses be budgeted and controlled by both sides? What are the most likely conditions under which both plaintiff and defendant would be willing to seek out of court settlement? The research determines the economic requisites of both a plaintiff's decision to litigate an issue and the corresponding defendant's decision on how to respond to the suit. These decisions are viewed as both commensurate and competitive with other managerial operating decisions, e.g., capital budgeting and market expansion, that make demands upon the firm's resources. Models from economics and learning theory are employed both to illustrate the relationship between expenditures on a civil suit and the probability of success and to show how litigation costs should be budgeted and controlled. The research also shows both the conditions under which it is advantageous for both sides to seek an out of court settlement and the means to estimate the probability of out of court settlements in civil litigation in general. This latter is shown under the most general conditions to be a minimum of 0.66 and to rise as the participants in the litigation become more risk averse.
Implicit Understandings in Channels of Distribution
Authors: Shugan Steven M. 
Published: November 2008

Formal agreements can be used to achieve coordination among channel members. These agreements work by exerting explicit control over the members who make the agreements. However, implicit understandings can be used as a partial substitute for more formal agreements. In this paper, we show that implicit understandings can develop as channel members learn about each other's behavior. We show that … This learning leads to the use of the implicit influence each channel member has over the other's behavior. The learning leading to an implicit understanding requires some form of experimentation or historical observation. This learning results in an oscillating retail price. When only one channel member learns the other's behavior, both channel members obtain greater profits than when neither member learns, and both channel members obtain less profits than when both members learn. However, the member who does not learn obtains more profits than the member who learns. We also show that … Implicit understandings result in greater channel profits than in their absence. Implicit understandings cannot fully substitute for an explicit contract. Implicit understandings result in a retail price which is higher than the price resulting from an explicit contract but lower than the price resulting in the absence of an implicit understanding. Implicit understandings develop as channel members learn each other's behavior. We demonstrate that the form of learning discussed in this paper is consistent with a somewhat general demand function. Finally, the paper provides some examples of both symmetrical learning, where both channel members learn at the same speed and asymmetrical learning where channel members learn at different speeds.
General Economic Equilibrium as a Unifying Concept in Energy-Economic Modeling
Authors: Weyant John P. 
Published: November 2008

In the pristine model of general economic equilibrium producers and consumers are assumed to take prices for their inputs and outputs as given. A market equilibrium solution is obtained when the prices of all products lead to equal amounts of supply and demand for each. The mathematical properties of this model provide a rich and powerful unifying foundation for much of modern microeconomic theory. However, in many practical applications it is difficult or impossible to develop the data, and formulate and solve the equations required to implement the model of general economic equilibrium in its most general form. In practice, generality of formulation is often sacrificed for ease of computation and interpretation. These tradeoffs allow the latest breakthroughs in optimization algorithms and computer technology to be applied in the analysis of important societal problems. A potential drawback associated with this otherwise desirable trend is that the analysis could become infatuated with the use of particular algorithms, and lose sight of the restrictive simplifying assumptions they imply. The present paper includes a comparison of the simplifying assumptions required in four of the most popular types of energy-economic models with respect to the model of general economic equilibrium. This comparison helps sharpen our appreciation for the tradeoffs between generalization of formulation and ease of computation and interpretation that are available. The concept of general economic equilibrium is employed to provide a common framework for four ostensibly different approaches to large-scale modeling: (1) variable-coefficient input-output theory, (2) process network methodology, (3) linear programming and (4) general nonlinear optimization. The similarities and the differences of the four approaches are isolated within this framework. This comparison makes both the absolute and the relative strengths and weaknesses of the models more transparent.
Heuristics in an Air Pollution Control Cost Model: The “AIRCOST” Model of the Electric Utility Industry
Authors: Silverman Barry G. 
Published: November 2008

A number of uncertainties associated with national air pollution policy are currently being analyzed by the United States Congress, the Environmental Protection Agency (EPA), and the Department of Energy (DOE) with the aid of a large-scale model of electric utility plant emissions under the 1983 Clean Air Act Amendments called AIRCOST. The AIRCOST methodology combines a “supply side” economics approach with detailed plant by plant models that result in substantial spatial and technological resolution. In fact, the resulting emissions projections are being used as input to separate air pollution transport models for the evaluation of "acid rain" impacts. This paper documents and partially validates this methodology with which a critical segment of U.S. air pollution policy has been and is continuing to be analyzed.
Consumption Experience and Sales Promotion Expenditure
Authors: Fornell Claes , Robinson William T. , Wernerfelt Birger 
Published: November 2008

An economic theory of habit formation through consumption learning is developed to explain order differences in relative sales promotion expenditures among brands. The theory applies to consumer brands in equilibrium markets, where consumer information from sources other than advertising, sales promotion, and previous consumption experience is negligible. Three propositions are derived from the theory: brands with more consumption experience (1) spend proportionately less on sales promotion as well as (2) on advertising and promotion combined, and (3) place proportionately more emphasis on advertising relative to sales promotion. These propositions are formulated as hypotheses and tested against empirical data from the PIMS project. It is found that the data are generally consistent with the propositions. In order to examine the robustness of the results, the hypotheses are subjected to three different empirical tests, each with different assumptions. The findings are shown to be reasonably robust with respect to these changes in assumptions.
An LP Planning Model for a Mental Health Community Support System
Authors: Leff H. Stephen , Dada Maqbool , Graves Stephen C. 
Published: November 2008

In this paper we develop a resource planning and allocation model for a mental-health community-support system. The intent of the model is to provide a tool to system managers and planners to support resource planning and allocation decision-making. More and more, mental health care is being delivered by a variety of community-based service agencies instead of single, comprehensive institutions. The service needs of a client population are continually changing, and depend upon the relative functioning of the population, which depends upon the efficacy of the services provided. The availability of resources is becoming scarcer, and is more closely scrutinized. Consequently, the system manager must attempt to apply the available resources as effectively as possible. We develop a conceptual framework for planning that includes aggregating patients according to their functional level and service needs, and defining “service package options” for each aggregate patient group. We also estimate the effect of giving a particular service package to a patient group, in terms of functional improvement or regression. The planning problem is then to assign service packages to aggregate groups over a multi-period planning horizon to maximize some measure of system welfare within the available resources. This planning problem is a linear programming problem that we illustrate using representative data.
A Comparison of Strategies to Dampen Nervousness in MRP Systems
Authors: Blackburn Joseph D. , Kropp Dean H. , Millen Robert A. 
Published: November 2008

This research examines the effectiveness of alternative strategies for dealing with the problem of order instability, or nervousness, which occurs in Material Requirements Planning systems. Nervousness can be particularly disruptive in multi-level production processes where a change in order size or timing at one level can result in changes at other levels. This study proposes and evaluates five different strategies for treating nervousness caused by the interaction of lot-sizing decisions and the planning horizon. Not evaluated here are the effects on order instability caused by demand uncertainty or supply and lead-time uncertainty. The five strategies examined are: (1) Freezing the schedule within the planning horizon, (2) Lot-for-Lot after stage 1, (3) Safety stocks, (4) Forecast beyond the planning horizon, and (5) Change cost procedure. A series of simulation experiments was conducted to test the effectiveness of the five strategies on schedule stability and system costs. The experiments were constructed to evaluate the impacts of various lot-sizing methods, the length of the planning horizon, setup and holding cost parameters and product assembly structure. The results indicate that when the source of nervousness is due to changes in decisions caused by a rolling planning horizon, safety stock and lot-for-lot approaches are not cost effective. Under most conditions, the strategies of incorporating a change cost to discourage schedule changes or freezing the schedule within the planning horizon appear to be dominant.
Virtual Positions and Power
Authors: Mackenzie Kenneth D. 
Published: November 2008

This paper discusses a class of natural organizational phenomena called virtual positions and links them to the enactment of power. Virtual positions involve three or more persons from different parts of an organization working together on a recurring (and usually major) task process. A virtual position is contrasted to a regular position in which an incumbent performs a set of task processes. There is no regular position for the task processes performed by a virtual position. Instead the set of individuals act as if they are a composite position. There are two types of virtual positions: regulated and unregulated. Regulated virtual positions usually take the form of committees, standing committees, and task forces. Unregulated virtual positions involve task processes which have been neither rationalized nor integrated with the Organizational Architecture. Virtual positions arise out of attempts to cope with organizational changes without having to redesign the organization. Given enough time a virtual position can be used to analyze change and to determine how it should be handled. But when changes occur at a more rapid rate than the virtual positions can be absorbed, they can spread rapidly. Thus an informal adaptive mechanism can lead to an accumulation of problems which can become maladaptive. Each virtual position involves the control of some task process and the possible leverage of this task process on others. Each virtual position participant has opportunity for access to information, other persons, and the possibility of enhancing his own position or preventing the enhancement of another's. When the virtual position involves major, recurring vulnerabilities, this control can be parlayed into organizational power. Virtual positions are viewed as arenas for power struggles in organizations. An example is given of the virtual positions in an actual community bank. The theory underlying the virtual positions is based on the continuing evolution of a theory of group structures. The concepts of process and task process are defined. A recently developed operationalization of the concept of interdependence is introduced. The notion of uncertainty is generalized. This leads to the development of uncertainty interdependence. Power is seen as the control of uncertainty interdependence. Virtual positions are viewed as the arenas in which uncertainty interdependencies can be resolved. Thus virtual positions are linked to the distribution and enactment of power in organizations. The theoretical discussion is based on a technology which is used in organizational design. Consequently, there exist means by which virtual positions can be identified and analyzed in real organizations. This paper links these analyses of virtual positions to the process of designing an organization.
Note—Patience is a Virtue in a Simple Model of Repetitively Joining a Queue
Authors: Bell Colin E. 
Published: November 2008

Each of n members of a finite customer population must weigh the rewards of service completion against the cost of waiting in a single exponential server queuing system. After completing service, a customer may re-enter the system. In attempting to maximize average return per unit time over an infinite horizon each customer must make a single decision, a choice of arrival rate which must then be used to determine the time until re-entry whenever the customer finishes being served. Equilibrium behavior in the resulting n person game is investigated. Equilibria exist involving a subset of the players who re-enter instantaneously after service while all others abstain from entry. In instances where all customers re-enter instantaneously, everyone could be made better off if it were possible to impose a non-instantaneous arrival rate.
Lead Users: A Source of Novel Product Concepts
Authors: von Hippel Eric 
Published: November 2008

Accurate marketing research depends on accurate user judgments regarding their needs. However, for very novel products or in product categories characterized by rapid change—such as “high technology” products—most potential users will not have the real-world experience needed to problem solve and provide accurate data to inquiring market researchers. In this paper I explore the problem and propose a solution: Marketing research analyses which focus on what I term the “lead users” of a product or process. Lead users are users whose present strong needs will become general in a marketplace months or years in the future. Since lead users are familiar with conditions which lie in the future for most others, they can serve as a need-forecasting laboratory for marketing research. Moreover, since lead users often attempt to fill the need they experience, they can provide new product concept and design data as well. In this paper I explore how lead users can be systematically identified, and how lead user perceptions and preferences can be incorporated into industrial and consumer marketing research analyses of emerging needs for new products, processes and services.
A Survey of Exact Algorithms for the Simple Assembly Line Balancing Problem
Authors: Baybars İlker 
Published: November 2008

In this survey paper we discuss the development of the simple assembly line balancing problem (SALBP); modifications and generalizations over time; present alternate 0-1 programming formulations and a general integer programming formulation of the problem; discuss other well-known problems related to SALBP; describe and comment on a number of exact (i.e., optimum-seeking) methods; and present a summary of the reported computational experiences. All models discussed here are deterministic (i.e., all input parameters are assumed to be known with certainty) and all the algorithms discussed are exact. The problem is termed “simple” in the sense that no “mixed-models,” “subassembly lines,” “zoning restrictions,” etc. are considered. Due to the richness of the literature, we exclude from discussion here (a) the inexact (i.e., heuristic/approximate) algorithms for SALPB and (b) the algorithms for the general assembly line balancing problem (including the stochastic models).
Financial Futures Hedging Via Goal Programming
Authors: Sharda Ramesh , Musser Kathryn D. 
Published: November 2008

This paper presents multiperiod, multiple objective goal programming as an alternative to the more conventional hedge ratio approaches to financial futures hedging. The described model offers the potential benefits of: (i) simultaneous achievement of multiple hedge-related objectives (i.e., minimization of transactions and margin opportunity costs; regulation of cash flow, and maximization of profits accruing from both the cash and futures positions); and (ii) periodic modification and updating of the futures position, as suggested by actual, observed prices and interest rates, throughout the hedging period. To assess its overall effectiveness, the model was applied to develop appropriate hedging strategies for three separate time periods, each representing a unique interest rate trend (i.e., upward movement, downward movement, and no change). Since real-world implementation of the model requires the use of forecast data, independent forecasts of both cash and futures prices were generated via (1) moving average, (2) exponential smoothing, and (3) random walk techniques. In progressing through each of the 13-week time periods, all forecasts were updated with the previous weeks' actual price data. Revised forecasts and actual price data were then incorporated into the model constraints on a weekly schedule. This approach, in essence, provided weekly futures activity recommendations based on the most recent price and interest rate developments observed at any point during the hedging period. The realized gains or losses were then compared to the previously-derived “perfect foresight” model results and to the traditional hedge ratio results. This allowed for evaluation of the model's effectiveness under varying forecast methods and varying interest rate trends. The results show that the goal programming model outperformed other strategies in most cases.
A Model for the Distribution of the Number of Bids on Federal Offshore Oil Leases
Authors: Engelbrecht-Wiggans Richard , Dougherty Elmer L. , Lohrenz John 
Published: November 2008

Not all Outer Continental Shelf (OCS) federal oil leases receive the same number of bids. Indeed, while some leases receive over a dozen bids, many others receive no bids at all. This leads to uncertainty in the number of bids a lease will receive—uncertainty of potential concern to both bidders and bid takers. We develop a model that suggest there are three fundamentally different types of leases—those with “no,” “low,” and “high” competition. This provides a basis for bidders and bid takers to explicitly account for some of the differences among leases when preparing bids and when evaluating the bidding. Although we specifically study only OCS federal oil leases, our overall approach and insights should apply equally well to many other situations with uncertain numbers of bids, including mineral leasing in general, as well as military procurement and construction contracting.