摘要:

This study seeks to highlight construct measurement issues in information systems (IS) research. It describes the normative process of construct measurement and identifies the difficult problems involved in measurement and some ways in which these difficulties may be overcome. An illustrative construct‐operationalization study in the area of strategic systems outlines how the normative guidelines may be applied to IS. Some specific recommendations for IS include developing a preliminary model of the construct even if there is little previous measurement research, devoting greater attention to predictive validity because a lack of theories in IS precludes the examination of nomological validity, verifying the assumptions underlying the computation of an overall index, and examining the measurement properties of the inde

ISSN:0011-7315    

DOI:10.1111/j.1540-5915.1991.tb01274.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The management of queues is a very important aspect of service operations management. One way to enhance the queueing experience is to provide customers with the most informative and certain estimate of anticipated wait time. This paper develops such a measure—referred to as the conditional wait‐time interval (CWTI)—for queueing systems with exponentially distributed service times. It is especially applicable at the operational level of an organization since it utilizes the most current information on the status of the system (number of customers in the queue at arrival). CWTI is also based on two risk factors that consider the chance a customer's actual wait time is outside of the estimated range. This paper also provides a graphical means to display multiple

ISSN:0011-7315    

DOI:10.1111/j.1540-5915.1991.tb01275.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Most studies in multiechelon inventory systems have concentrated on understanding the specific aspects of a system's behavior. The problem of optimal policy computation has largely been ignored. In this paper, we investigate a two‐echelon inventory system experiencing stochastic demand and a pull system of inventory allocation. Both echelons use an order‐up‐to‐level type control policy. A mathematical model is developed to determine the optimal order level at all echelons and validated through simulation. Two simple algorithms to locate the optimum solution are presented. The use of graphical tools in optimal policy calculation is also di

ISSN:0011-7315    

DOI:10.1111/j.1540-5915.1991.tb01276.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

This paper investigates the mathematical programming (MP) approach for decision making and cost allocation in the context of joint products. Through analysis of the MP approach to marginal‐value‐based cost allocations, an algorithm is developed to show that the allocations contain two elements: an element that is specific to individual joint products due to differences in demand elasticities, and an element based on relative adjusted sales values. If demand elasticities are identical for all joint products, then the traditional sales value method will generate the same cost allocation as the MP method. The new algorithm, the demand‐adjusted‐sales‐value algorithm (DASV), is especially helpful for solving the MP model with linear demand functions. The DASV algorithm provides an easy way to generate costs that are useful for optimal decisi

ISSN:0011-7315    

DOI:10.1111/j.1540-5915.1991.tb01277.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The importance of sensitivity analysis information in linear programming has been stressed in the management science literature for some time. Indeed, Gal [3] has devoted an entire text to just this issue. Linear programs with common inputs (cost coefficients or right‐hand‐side values) present a problem in that classical sensitivity analysis does not allow for the simultaneous changes required to determine the sensitivity of these models to common inputs. We first survey the approaches previously developed for simultaneous‐change sensitivity analysis and cast them in the framework of the special common input case. These general techniques are compared to a simple aggregate variable technique that has not received attention in the liter

ISSN:0011-7315    

DOI:10.1111/j.1540-5915.1991.tb01278.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Linear programming discriminant analysis (LPDA) models are designed around a variety of objective functions, each representing a different measure of separation of the training samples by the resulting discriminant function. Aseparation failureis defined to be the selection of an “optimal” discriminant function which incompletely separates a pair of completely separable training samples. Occurrence of a separation failure suggests that the chosen discriminant function may have an unnecessarily low classification accuracy on the actual populations involved. In this paper, a number of the LPDA models proposed for the two‐group case are examined to learn which are subject to separation failure. It appears that separation failure in any model can be avoided by applying the model twice, reversing group designa

ISSN:0011-7315    

DOI:10.1111/j.1540-5915.1991.tb01279.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Inventory management has undergone significant philosophical changes in recent decades such as the advent of the zero inventory concept. However, as attractive as the concept of minimal inventories may be, it is often unrealistic in application. Attention to basic features of inventory control systems such as order quantities, base stock levels, and reorder points remain crucial to ensure customer service at minimal cost. A nonlinear optimization model for determining base stock levels in a multi‐echelon inventory network is presented. Lagrangian relaxation results in (1) newsboy‐style relations that provide the optimal solutions, and (2) instantaneous shadow prices for the budget constraint. Sensitivity analysis of this model will facilitate making decisions concerning the desired investment in inventory for the entire system. This model may be solved on standard nonlinear programming software and is generalizable to problems in both production and distribution setti

ISSN:0011-7315    

DOI:10.1111/j.1540-5915.1991.tb01280.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

This paper addresses the problem of sequencing in decentralized kanban‐controlled flow shops. The kanban production control system considered uses two card types and a constant withdrawal period. The flow shops are decentralized in the sense that sequencing decisions are made at the local workstation level rather than by a centralized scheduling system. Further, there are no material requirements planning (MRP)‐generated due dates available to drive dispatching rules such as earliest due date, slack, and critical ratio.Local sequencing rules suitable for the decentralized kanban production‐control environment are proposed and tested in a simulation experiment. These rules are designed so that they can be implemented with only the information available at the workstation level. Example sequencing problems are used to show why the shortest processing time rule minimizes neither average work‐in‐process inventory nor average finished‐goods withdrawal kanban waiting time. Further, it is shown how work station supervisors can use the withdrawal period, in addition to the number of kanbans, to manage work‐in‐proc

ISSN:0011-7315    

DOI:10.1111/j.1540-5915.1991.tb01281.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Providing proper incentives to firm managers is increasingly important in the current competitive environment. Analytical research has suggested that evaluating a manager's performance relative to that of a peer group, in conjunction with standard‐based pay, can induce efficient risk‐sharing between firm owners and managers while maintaining the latter's incentives to exert effort. To date, direct empirical tests of this proposition have not been reported.This study uses a laboratory experiment to test the effect of relative performance evaluation on the risk‐aversion of delegated investment decisions. Project‐specific risk is operationalized using operating leverage, in part because the variability of a project's operating profits generally increases with this variable, and in part because many of the new manufacturing approaches held to be important to competitive advantage require significant capital investments and attendant increases in operating leverage. Across two levels of environmental uncertainty, subjects under a relative (as opposed to absolute) performance standard selected investments with significantly higher project‐specific risk. Also, as environmental uncertainty increased, subjects under an absolute standard significantly reduced the riskiness of their investments. In contrast, subjects shielded from environmental uncertainty by a relative standard chose investments of about equal riskiness under both low and high uncertainty conditions. If supported by future research, these findings would suggest that relative performance evaluation may reduce managers' reluctance to adopt risky capital investments, especially in firms operating in high‐risk economic or technological e

ISSN:0011-7315    

DOI:10.1111/j.1540-5915.1991.tb01282.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Current research studies in cellular manufacturing have considered environments constrained only by the machine resource, when in fact the flexibility of manufacturing cells is derived mainly from its allocation of the labor resource. This research specifically examines the labor resource in cellular manufacturing, also known as group technology (GT), through a series of simulation experiments on a hypothetical GT shop and recommends conditions under which different labor allocation strategies may be appropriate. The effects of various product routings and scheduling policies on labor allocation are also examined.

ISSN:0011-7315    

DOI:10.1111/j.1540-5915.1991.tb01283.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY