三参数区间灰数信息下系统属性约简方法

针对属性评价值为三参数区间灰数的不完备信息系统,提出了一种基于[θ]-灰色优势关系的信息系统属性约简方法。根据三参数区间灰数的定义,给出两个三参数区间灰数基于可能度的大小关系,在此基础上,构建方案属性值之间的一种[θ]-灰色优势关系,并结合可辨识矩阵,给出了这类不完备信息系统属性约简方法。应用实例表明了方法的合理性和有效性。     

基于改进的优势关系下的不完备区间值信息系统评估模型

优势粗糙集方法是研究不完备区间值信息系统的一种重要方法。针对当前不完备区间值信息系统研究中存在的问题,提出了两种新的优势关系,即上限优势关系和近似优势关系。在此基础上,研究了对象评估和不确定性度量问题,给出了不同优势关系间的区别与联系,最后利用具体算例加以说明。     

决策区间值信息系统的交互相容关系及属性约简

决策区间值信息系统的处理方法在解决实际问题中具有重要意义.定义了区间的相对包含度概念,进而提出区间的交互相似度、决策区间值信息系统的交互相容关系,从而克服了以往区间值信息系统方法忽略区间的交互关系的不足,提高了分类的准确性;讨论了交互相容关系下决策区间值信息系统的属性约简和相对属性约简,并给出了寻找约简和相对约简的具体操作方法.     

基于不完备区间值信息系统的决策粗糙集

在不完备区间值信息系统中,提出一种基于极大相容类的决策粗糙集模型。首先,针对不完备区间值信息系统中属性相似度存在的缺陷,对属性相似度进行改进。其次,在不完备区间值信息系统中,由于容差关系下建立粗糙集模型存在冗余度高、分类精度低的问题,采用极大相容类代替等价类,结合贝叶斯最小风险决策原则,建立决策粗糙集模型。经证明,基于极大相容类建立粗糙集模型可有效提高分类精度。最后,基于正域分布不变的原则提出基于区分矩阵的属性约简算法并将该算法应用于实例。     

不完备信息系统中属性的重要度及约简方法

在不完备信息系统中,基于相似关系的定义,讨论了属性相对于对象的重要度。通过聚合算子聚合属性相对于所有对象的重要度,可得到属性的重要度。根据属性的重要度,给出了不完备信息系统的一种属性约简方法。实例说明该方法可以减少属性约简的搜索空间并找到不完备信息系统的属性约简。     

优势关系下的区间值信息系统及其属性约简

针对区间值信息系统,提出一种新的优势关系,并定义了基于这种优势关系的信息系统的上、下近似集。通过可辨识矩阵的方法,提出了区间值信息系统的属性约简方法。通过实例验证该属性约简方法简便易行。     

不完备信息系统中基于限制容差关系的属性约简方法

决策表核属性的确定往往是信息约简的基础,然而以往的核属性约简方法大多是针对完备信息系统的。将完备信息系统中的属性核与属性序约简算法延伸至不完备系统,提出一种不完备信息系统中基于限制容差关系的属性约简方法。该方法通过构造限制容差关系下决策表的改进分辨矩阵来求得核属性,并将非核属性按直观影响分类质量的能力排序,能够保证得到的约简结果是相对最小约简。通过实验比较证明该方法可行、有效。     

基于不完备信息系统的三角模糊数决策粗糙集

在不完备信息系统中,针对用区间值表示一个未知参量时,整个区间内取值机会被认为是均等的,得到的结果可能会产生过大误差的问题,将三角模糊数引入到决策粗糙集中,提出了一种基于不完备信息系统的三角模糊数决策粗糙集。首先,定义了一种描述不完备信息的相似关系;然后,针对不完备信息系统中的缺失值,利用三角模糊数来获取损失函数,构建了三角模糊数决策粗糙集模型;实例表明,本文提出的方法不仅能够弥补用区间数表示的不足,而且可以突出可能性最大的主值,从而减少分类误差。     

不完备联系度粗糙集模型的知识约简

知识约简是粗糙集理论的重要研究内容之一。在不完备信息系统中,对联系度粗糙集模型的研究比较深入,但极少涉及知识约简问题。该文在进一步改进联系度粗糙集模型的基础上,研究该模型的知识约简。针对改进模型,提出多种知识约简定义,给出了这些约简之间的关系。通过定义初等分辨矩阵和属性重要度,介绍一种分配约简算法。实例分析说明了算法的有效性。     

不完备区间值信息系统的安全评估?

针对不完备区间值信息系统(IIIS)多属性群决策的“瓶颈”问题,讨论基于广义优势关系粗糙集的不完备区间值信息的处理方法,并改进分类质量的概念,在结合层次分析法形成一致性判断矩阵的基础上,确定群决策中各决策者的权重,实现对IIIS的综合安全评估。实例分析说明了该方法的有效性和实用性。     

Information systems practice, education and research

Abstract. The launch of a new journal in information systems prompts thought and debate concerning the state of the subject area and some contemplation on its past and future. This introductory paper reflects the views of the editors, views which will not be shared by all. We find a wide spectrum of interpretations and experiences concerning the nature of information systems and this wide range of views is both a strength and a weakness. It is a weakness in the sense that it is very difficult to put boundaries around the area and establish common definitions and accepted norms. The latter are usually associated with more stable and established disciplines that have accepted underlying theories. It is a strength in the sense that the wide variety of views, experiences and background subjects adds richness to the discipline. From the point of view of the Journal of Information Systems this should mean a wide variety of interesting topics from which we can draw. Our paper begins with an introduction to the debate about the nature of information systems, a debate which is continued in the following paper. We also give an overview of practice, education and research in information systems. In order to keep the paper to a reasonable length, this overview will necessarily be selective and will probably be Anglocentric.     

Organizational information management strategies

Abstract. Information technology is a key factor in competitiveness. Business managers increasingly have to make decisions in this field. Their involvement in planning and decision making should be active and genuine. There are numerous methods to support information systems planning and implementation. This study focuses on the organizational approach to generating plans. An interactive framework for evolutionary information systems planning is presented together with the results of applying this framework in six organizations. The author has been working with these organizations very intensively, using an action research approach. The main emphasis is on the success of the organizational method of creating information management strategies. The main finding is that an interactive way of generating strategies is not enough. The role of internal 'project champions' in both planning and implementation is extremely important. Outside facilitators cannot replace their contribution.     

Reflections on information systems practice, education and research: 10 years of the Information Systems Journal

This paper celebrates the 10‐year anniversary of the Information Systems Journal (ISJ) and the Editors reflect on the papers that have been published over that period and the changes that have occurred in the discipline of information systems. In the opening paper of ISJ, we suggested that the ‘launch of a new journal in information systems prompts thought and debate concerning the state of the subject area and some contemplation of its past and future’. We discussed three areas of this ‘not‐yet‐established discipline’: practice, education and research. In this follow‐up paper, we forgo our convention of ISJ editors not publishing in the Journal. We examine the issues raised in the first paper and consider what has happened in the intervening years as charted in the ISJ. The overview is necessarily selective, probably Anglocentric (with, perhaps, a slight Francophile tinge), sometimes downright opinionated, as well as over‐estimating, perhaps, the contribution of one particular IS journal.     

Design, development and implementation of a global information warehouse: a case study at IBM

The characteristics of a global information warehouse (GIW) can be understood with reference to the three dimensions implied by the three words in its name. These dimensions are boundary of the system, semiotic level of the objects in the system, and organization of objects in the system, corresponding to the terms 'global', 'information' and 'warehouse', respectively. This paper defines these three dimensions and describes the system characteristics that flow from the definitions. These characteristics also highlight the issues involved in the design, development and implementation of GIWs. The case study following the discussion of the three dimensions illustrates these issues.     

On the discipline of information systems

Abstract. Although information systems is growing rapidly, it has little theoretical clarity. An article in the Times Higher Education Supplement of March 1989 by Liebenau and Backhouse sparked a debate on the character of information systems as a discipline. This paper reviews that debate, bringing out the main points of many of the discussants, and presents an analysis which is intended to carry the discussion further in order to help clarify and to galvanize opinion.     

The strategic dimension of transactional information systems: some organizational implications

Abstract. Often information systems (IS) are classified in three groups: (a) transactional, used mainly for co-ordination and resource allocation purposes at the operational level of a company; (b) tactical, often employed to support the resource procurement activities typical of middle management; and (c) information systems for strategic decision making, designed to help in the planning and strategy design processes which are the direct responsibility of top management. In general, the amount of care and management attention that companies give to these different types of systems is proportional to their position in this hierarchy: little attention is devoted to the mundane transaction-pushing systems and exquisite care is put into developing the sophisticated decision making aid for the CEO and his/her staff.
The IS/IT literature has been reporting quite commonly cases in which companies have attained or lost great competitive advantages by way of their transactional information systems [for example, Emery Worldwide, Baxter Healthcare ASAP system, and Frontier Airlines]. The aim of this paper is to identify actions that companies can take to realize potential benefits of their IS, in particular from their low-level, transactional IS.
Among other actions, we will conclude that companies would be better off if they: (a) have the IS department at the right place in the organization, staffed with people knowledgeable about the basic nature of the business in which the company is engaged; (b) are sensible to what can be called 'strategic maintenance' of systems, (c) set up a formal procedure for IS planning to ensure coherence between IS plans and business plans, derived, in turn, from business strategy, and (d) keep abreast of the relevant technology.
Several examples taken from European companies are used to illustrate these conclusions.     

IS Strategy and IS Contribution: CEO and CIO Perspectives

This research compares views of CEOs and CIOs in the same organization about the contribution of IS to their organization and about the IS strategy that produced the contribution. The executives agree about the extent of IS contribution, but disagree about how IS strategy produces it. CEOs view analysis and proactiveness strategies as the two top keys to doing so, whereas CIOs see innovativeness and aggressiveness strategies as the two top keys.     

Process and reality in information systems benefit analysis

The identification of the potential benefits of a proposed information system project is a very challenging and important task. However, little research describes how this is actually carried out. The objective of this research was to answer the core question: how do organizations identify the expected benefits of proposed IS projects? To accomplish this objective, the authors studied 24 projects by interviewing 20 subjects from 13 organizations. Based on these interviews, a model of the benefit identification process was formulated showing it to be a set of loosely defined, overlapping, iterative activities. The study suggests that, despite great uncertainty about the potential benefits, proposers were compelled to use the benefit identification process to persuade the organization to be committed to the project. This effort to build commitment under great uncertainty may contribute to the overstatement or understatement of expected benefits. The study offers managers an understanding of the process and guidance for carrying it out. It also suggests that future researchers validate the model, use it to help identify best practices and test related hypotheses.     

Information systems ‘in the wild’: supporting activity in the world

One of the most important determinants of managerial effectiveness in achieving organisational objectives is the success in influencing subordinates, lateral peers and supervisors through influence tactics. However, little attention has been paid to the use of a communication medium in the context of influence tactics. Our objective is to study the frequency of these dyadic influence tactics on diverse communication media. The study involves a questionnaire-based survey conducted on Spanish post-graduate students who had been working in medium-sized or large companies during the last 2 years or more. The results suggest that the richness of the medium explains most similarities and differences in the frequency of influence tactics for different communication media. Furthermore, in the study of hard influence tactics in communication media with similar richness, it is necessary to introduce social aspects and the level of surveillance in order to explain it fully. This study helps managers to understand the relationships between influence tactics and the use of communication media in order to improve their communication effectiveness.     

An integrated programme for critical thinking in information systems research

Abstract. This paper sets out to demonstrate that critical systems thinking can provide the necessary theoretical background for the development of an integrated approach to critical thinking in information systems research. Critical systems thinking is itself a relatively new development in management science. By about 1990, however, it had established itself on the basis of five commitments; to critical awareness, to social awareness, to complementarism at the level of methodology, to complementarism at the level of theory, and to human well-being and emancipation. The paper discusses these critical systems commitments and shows that each of them has, at one time or another, received attention in the literature on information systems. Addressing them as a whole, as in critical systems thinking, can yield an integrated programme for critical thinking in information systems research.