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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Financial fraud detection by using grammar-based multiobjective genetic programming with ensemble learning

LI, Haibing 08 April 2015 (has links)
Financial fraud is a criminal act, which violates the law, rules or policy to gain unauthorized financial benefit. As an increasingly serious problem, it has attracted a lot of concerns. The major consequences are loss of billions of dollars each year, investor confidence and corporate reputation. Therefore, a study area called Financial Fraud Detection (FFD) is obligatory, in order to prevent the destructive results caused by financial fraud. In general, traditional modeling approaches are applied and based on pre-defined hypothesis testing of causes and effects for FFD problems. In addition, the evaluation criteria are often based on variable significance level or Goodness-of-fit only. FFD has many common features like other data mining problems. It has accumulated vast amounts of data records of different forms (e.g. financial statements or annual reports) over a period of time. It is very difficult to observe the interesting information just by relying on traditional statistical methods. However, data mining techniques can be used to extract implicit, previously unknown and potentially useful patterns, rules or relations from massive data repositories. Such discovered patterns are appropriate to executive leadership, stakeholders and related regulatory agencies to reduce or avoid the losses. As real-life problems, it is not sufficient for FFD to consider only a single criterion (e.g. Goodness-of-fit or accuracy). Instead, FFD can also seek multiple objectives (e.g. accuracy versus interestingness). It is not easy to consider multiple objectives at the same time unless applying combination methods (e.g. linear combination) by assigning different weights to present the importance for each criterion by using data mining techniques with a single evaluation criterion. For example, accuracy is more important than interestingness with weights of 0.9:0.1. But it is still difficult to decide the appropriate or exact values for weights. There-fore, multi-objective data-mining techniques are required to tackle FFD problems. In this study, FFD is targeted, and comprehensively evaluated by a number of methods. The proposed method is based on Grammar-Based Genetic Programming (GBGP), which has been proven to be a powerful data mining technique to generate compact and straightforward results. The major contributions are three improvements of GBGP for FFD problems. First, multi-criteria are considered by integrating the concept of multi-objectives into GBGP. Second, minority prediction is applied to demonstrate the class prediction with unmatched rows in their rules. Lastly, a new meta-heuristic approach is introduced for ensemble learning in order to help users to select patterns from a pool of models to facilitate final decision-making. The experimental results showed the effectiveness of the new approach in four FFD problems including two real-life problems. The major implications and significances of the study can concretely generalize for three points. First, it suggests a new ensemble learning technique with GBGP. Second, it demonstrates the usability of classification rules generated by the proposed method. Third, it provides an efficient multi-objective method for solving FFD problems.
202

An improved model for trust-aware recommender systems based on multi-faceted trust

ZHU, Peihu 19 August 2016 (has links)
As customers enjoy the convenience of online shopping today, they face the problem of selecting from hundreds of thousands of products. Recommender systems, which make recommendations by matching products to customers based on the features of the products and the purchasing history of customers, are increasingly being incorporated into e-commerce websites. Collaborative filtering is a major approach to design algorithms for these systems. Much research has been directed toward enhancing the performance of recommender systems by considering various psychological and behavioural factors affecting the behaviour of users, e.g. trust and emotion. While e-commerce firms are keen to exploit information on social trust available on social networks to improve their services, conventional trust-aware collaborative filtering does not consider the multi-facets of social trust. In this research, we assume that a consumer tends to trust different people for recommendations on different types of product. For example, a user trusts a certain reviewer on popular items but may not place as much trust on the same reviewer on unpopular items. Furthermore, this thesis postulates that if we, as online shoppers, choose to establish trust on an individual while we ourselves are reviewing certain products, we value this individual’s opinions on these products and we most likely will value his/her opinions on similar products in future. Based on the above assumptions, this thesis proposes a new collaborative filtering algorithm for deriving multi-faceted trust based on trust establishment time. Experimental results based on historical data from Epinions show that the new algorithm can perform better in terms of accuracy when compared with conventional algorithms.
203

Joint lead time and price quotation : dynamic or static?

ZHANG, Guo 25 August 2015 (has links)
Intuitively, quoting dynamic lead time and price to customers based on real-time system state provides more efficient capacity utilization and increases revenue compared with quoting static lead time and price. However, dynamic quotation may require higher operational costs for the firm and it is often inconvenient to customers. This study aims to compare dynamic and static lead time and price quotations under fixed capacity and different potential demand rates. We hypothesize that there exists a potential demand rate under which the additional costs of dynamic quotation and the additional profit from dynamic quotation are equal. Thus static quotation may yield better performance under certain potential demand rates. We use an M/M/1 queuing model to model the supply system of a firm and formulate profit maximization models in an average reward criterion under both static and dynamic lead time and price quotations. Numerical analyses are presented to illustrate performances of both static and dynamic lead time and price quotation and thus find the threshold potential demand rate. Besides, we study performance of two different kinds of dynamic lead time quotation and find that when firm can decide their price, performance of dynamic lead time quotation is good enough and when firm cannot decide their price, the dynamic lead time quotation is good only when lead time sensitive factor is small and potential demand rate is big.
204

Systems engineering design for operations directorate administrative information system

Hasegawa, Marnie Tardieu 24 October 2009 (has links)
This project addresses an administrative information system for the Operations Directorate (0D) within federal government agency (which is referred to as the "Agency"). The OD was formed two years ago to combine similar tasks under one directorate. When the 00 was formed there was insufficient time to properly address the information system and many of the OD personnel did not have a clear understanding of their own functional requirements. Now two years later, the OD management would like to incorporate an information system that satisfies all of the users requirements. <p>This project addresses the analysis and design alternatives to the development of an information system that satisfies the OD requirements. The requirements encompass not only the users requirements but logistic, maintenance, environmental and security requirements. The OD information system integrates the concepts and techniques of System Engineering Design. <p>The research encompassed the class work from the System Engineering program, to include System Engineering, Applied System Engineering, Management Information Systems, Human Factors Engineering, Statistics. Software Engineering, and Productivity. These engineering and mathematical disciplines integrate to form the system engineering approach. <p>Three design alternatives were developed from the users requirements and current system configuration. Using the system engineering analysis, a design alternative was chosen based on the users requirements, system life cycle cost and OD yearly budget considerations. <p>The solution is a concise project detailing the analysis, and design of the 0D Information System. The intent of this project is to provide a methodology in developing an information system for this government agency. The functional, technical and operational aspects of the system integrate together to form the system. <p>The goal is to ensure the system provides a more productive, technically efficient, reliable, and user friendly system. The productivity of the system is the measure of the number and quality of reports, publications, and presentations. The system is considered technically efficient when the production of output has taken advantage of all available technology to minimize the inputs of production. A reliable system is one that fails infrequently and recovers quickly when it does fail. A user friendly system is a system where the user interface has been developed to point where an average person can perform the required tasks quickly and without software error. <p>The measuring of the the system in terms of Mean Time Between Failure (MTBF), and Mean Down Time (MDT), user and management feedback determines whether the system has achieved it's defined goals. / Master of Science
205

An Assessment of Computer Education in the Business School: A Jungle Within a Jungle

Yasin, Mahmoud M., Green, Ronald F., Wafa, Marwan 01 January 1989 (has links)
With the increasing role of computer information systems in the business community, it is imperative that students be properly trained to meet the requirements of a computerized business environment. This article evaluates the role of business schools in preparing students to meet the challenges of the information age. It also addresses how the field of knowledge commonly referred to as Management Information Systems (MIS) interfaces with the "Management Theory Jungle" (Koontz, 1961). Three models that attempt to clarify how computers and information processing systems are viewed from business, academic, and theoretical perspectives are presented. The article concludes that the lack of enforceable standards in computer business education is the primary factor contributing to the existence of an MIS jungle within the management theory jungle. Recommendations for untangling this jungle are provided for the business and academic communities.
206

Advanced Manufacturing Technology Adoption and Performance: The Role of Management Information Systems Departments

Small, Michael H., Yasin, Mahmoud 08 September 2003 (has links)
This study uses information obtained from the advanced manufacturing technology (AMT) literature to develop a conceptual framework that seeks to illustrate the impact of the management information systems (MIS) department on the different facets of AMT adoption. A detailed survey instrument was administered to a cross-section of manufacturing firms in the USA to collect the data required to test five hypotheses relating to the efficacy of this framework. The results of this study indicate that the proposed framework is particularly useful in explaining the role of MIS departments in firms that are attempting to integrate advanced process and information technologies. This finding and other results of this study and their Implications are discussed.
207

Information Retrieval Using the Constructivist's Approach to Get the Most Out of the Internet

Shukla, Ishani 01 December 2009 (has links)
The constructivist's theory and its application to information retrieval from the Internet was reviewed. The main aim of the study was to devise and test an approach with which the most relevant information could be easily and efficiently extracted from the Internet. The impact of a judicious choice of the keywords to retrieve information, according to the particular approach to be implemented as well as the importance of speed reading as an additional technique to improve information retrieval, was compared and critically analyzed. The study was based on information retrieval from www.google.com and www.images.google.com and focused on real-life examples and goal-directed searches. After a careful selection, the criteria used for evaluation were factors such as data quality, accuracy, integrity, and speed of retrieval. These factors helped to determine how useful the constructivist theory could be in information retrieval if it was to be applied in combination with speed reading and traditional approaches.
208

Coaching the Self: Identity Work(Ing) and the Self-Employed Professional

Ruane, Sinéad Grace 01 February 2013 (has links)
Identity has long been a prolific research interest for organizational scholars. Its popularity can be attributed to the development of post-bureaucratic organizations, where control is no longer achieved through external forms (i.e. rules and procedures), but rather, "softer" mechanisms, such as organizational culture and values. Examining identity therefore becomes crucial for understanding how employees internalize organizational goals to exhibit desired behaviors. While the predominant approach has been to analyze how organizations help shape, control, and regulate member identity, this project calls into question the assumption of organizational employment to explore the micro-processes of identity construction among a growing class of worker in the U.S.: the self-employed professional. This investigation is grounded in the world of personal coaching, an emerging profession organized largely by self-employment. Between 2007-2011, I immersed myself in the "field" of coaching, generating data via ethnographic methods--i.e. participant observation, in-depth interviews, informal interactions--and secondary archival sources. Applying a critical interpretive lens to conceptualize identity not as a "thing" but as an ongoing social accomplishment, the analysis reveals three main insights. First, intense identity working was provoked by tensions and anxiety arising from conflicts, contradictions, and challenges, as informants tried to construct a positive identity as a self-employed professional, while simultaneously performing vital (and mostly unrecognized) identity work for the wider coaching profession. Second, since "doing" identity and material conditions are mutually constitutive, identity efforts can be categorized as having a profitable, proficient, or pragmatic orientation; I contend that this typology is applicable to other self-employed professionals. Third, as a socially negotiated process, identity working is one which recruits many participants--both within and outside of the coaching community. Furthermore, geographically-dispersed members actively regulate and control each other's identities to maintain professional standards, via new organizing forms, like social media. This investigation contributes to knowledge about the nuances of identity working, and linkages between such micro-processes and the wider historical, socio-economic conditions. Extending beyond the coaching profession, the data produced serve as a contextual exemplar for exploring how individuals navigate the restructuring of labor and changing employment relations, which increasingly characterize the "new world of work."
209

Bounding Methods for Facilities Location Problems

Dowling, Paul 09 1900 (has links)
This thesis has been partially OCRed. Please contact for further accessibility requests. / Several methods have been proposed and tested for calculating lower bounds on the objective function of facilities problems. These methods contribute to the efficiency of iterative solution methods by allowing the user to terminate the computation process when the objective function comes within a predetermined fraction of the optimal solution. Two of the existing bounding methods have been presented only for single facility location models with Euclidean (straight-line) distances. One of these methods uses the dual of the single facility location model to compute a lower bound. This thesis introduces a method for generating a feasible dual solution from any primal solution by means of a projection matrix. The projection matrix method is applied to single and multi-facility models. The second bounding method, which involves the solution of a rectilinear distance model to obtain a lower bound, is extended in this thesis to include a generalized, distance function and the multi-facility situation. Computation results for the two new bounding methods are compared with several existing bounding methods. These results should aid practitioners in selecting an appropriate bounding method for an iterative solution method to a facilities location problem. / Thesis / Doctor of Philosophy (PhD)
210

What Do Physicians Want? Information Technology Acceptance And Usage By Healthcare Professionals

Ilie, Virginia 01 January 2005 (has links)
This study builds on the theory of planned behavior, institutional and innovation diffusion theories to investigate physicians' responses to introduction of electronic medical records (EMR) in large healthcare organizations. Using a case study methodology, we show that physicians' attitudes towards using EMR are influenced by their perceptions of EMR complexity, relative advantage, compatibility with professional beliefs and individual predisposition to change. Specifically, we found that EMR usability characteristics such as system interface, "navigation," "search" and "speed" are major dimensions underlying physicians' perceptions of EMR complexity. To the extent that navigating and searching for clinical results are seen as difficult, physicians' perceptions of the complexity of using EMR are enhanced, with the result of physicians forming more negative attitudes towards EMR and using EMR less. Accessibility to EMR (i.e. logging in) and availability of hardware are two emergent constructs. These factors are immediate barriers for physicians not using EMR or using EMR minimally. At the same time, these barriers contribute to impacting physicians' perceptions that EMR is difficult to use and disadvantageous (i.e. time inefficient) compared to the paper chart. Results also show that most EMR usage at Alpha is rather "shallow." Physicians tend to use data-retrieval EMR minimally, mainly to supplement the paper chart. The availability of this "competing artifact," that is much easier to use and conveniently located near a patient's room limits the extent to which physicians use EMR at Alpha. Use of an imaging EMR system (EMR3) is more committed. EMR3 is used to replace the "old way" of accessing films. Lack of accessibility and hardware barriers, the relative advantage of EMR3 and other system usability considerations contribute to physicians using this system more faithfully. As regards the question "what do physicians want?" it seems that physicians want a system that that is easy to access and simple to use but most importantly, a system that they can directly identify with, an EMR that is personally relevant. In order to promote a "deeper" level of EMR usage, the benefits of EMR need to be emphasized to physicians while any potential costs or barriers reduced or eliminated.

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