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Singapore Management University Report To Stakeholders 2009 - 2010, Singapore Management University Jan 2009

Singapore Management University Report To Stakeholders 2009 - 2010, Singapore Management University

Report to Stakeholders

Since our inauguration in 2000, we have grown from a simple idea of a group of pioneers who came together - inspired by a new philosophy and approach towards undergraduate education - into a progressive, globally respected university that is widely recognised as a change agent and catalyst for innovation. Over the past 10 years, SMU has proven to be a successful experiment in Singapore’s efforts to strengthen and diversify its higher education sector. We have lived up to our promise of making a difference to our society through the graduates we have produced, through our engagement with the local …

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A Cluster Identification Framework Illustrated By A Filtering Model For Earthquake Occurrences, Zhengxiao Wu Jan 2009

A Cluster Identification Framework Illustrated By A Filtering Model For Earthquake Occurrences, Zhengxiao Wu

Research Collection School of Economics

A general dynamical cluster identification framework including both modeling and computation is developed.The earthquake declustering problem is studied to demonstrate how this framework applies.A stochastic model is proposed for earthquake occurrences that considers the sequence of occurrencesas composed of two parts: earthquake clusters and single earthquakes. We suggest that earthquake clusterscontain a “mother quake” and her “offspring.” Applying the filtering techniques, we use the solution offiltering equations as criteria for declustering. A procedure for calculating maximum likelihood estimations(MLE’s) and the most likely cluster sequence is also presented.

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A Centered Index Of Spatial Concentration: Axiomatic Approach With An Application To Population And Capital Cities, Filipe R. Campante, Quoc-Anh Do Jan 2009

A Centered Index Of Spatial Concentration: Axiomatic Approach With An Application To Population And Capital Cities, Filipe R. Campante, Quoc-Anh Do

Research Collection School Of Economics

We construct an axiomatic index of spatial concentration around a center or capital point of interest, a concept with wide applicability from urban economics, economic geography and trade, to political economy and industrial organization. We propose basic axioms (decomposability and monotonicity) and refinement axioms (order preservation, convexity, and local monotonicity) for how the index should respond to changes in the underlying distribution. We obtain a unique class of functions satisfying all these properties, defined over any n-dimensional Euclidian space: the sum of a decreasing, isoelastic function of individual distances to the capital point of interest, with specific boundaries for the …

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Modeling The Impact Of Test Anxiety And Test Familiarity On The Criterion-Related Validity Of Cognitive Ability Tests, Charlie L. Reeve, Eric D. Heggestad, Filip Lievens Jan 2009

Modeling The Impact Of Test Anxiety And Test Familiarity On The Criterion-Related Validity Of Cognitive Ability Tests, Charlie L. Reeve, Eric D. Heggestad, Filip Lievens

Research Collection Lee Kong Chian School Of Business

The assessment of cognitive abilities, whether it is for purposes of basic research or applied decision making. is potentially susceptible to both facilitating and debilitating influences. However, relatively little research has examined the degree to which these factors might moderate the criterion-related validity of cognitive ability tests. To address this gap, we use Classical Test Theory formulas to articulate how test anxiety and test familiarity can influence observed scores, observed score variance, and most importantly, the criterion-related validity of observed scores. The resulting equations reveal that understanding the influence of test anxiety and test familiarity on criterion-related validity coefficients requires …

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Semiparametric Cointegrating Rank Selection, Xu Cheng, Peter C. B. Phillips Jan 2009

Semiparametric Cointegrating Rank Selection, Xu Cheng, Peter C. B. Phillips

Research Collection School Of Economics

Some convenient limit properties of usual information criteria are given for cointegrating rank selection. Allowing for a non-parametric short memory component and using a reduced rank regression with only a single lag, standard information criteria are shown to be weakly consistent in the choice of cointegrating rank provided the penalty coefficient C(n) -> infinity and C(n)/n -> 0 as n -> 8. The limit distribution of the AIC criterion, which is inconsistent, is also obtained. The analysis provides a general limit theory for semiparametric reduced rank regression under weakly dependent errors. The method does not require the specification of a …

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Event-Detecting Multi-Agent Mdps: Complexity And Constant-Factor Approximation, Akshat Kumar, S. Zilberstein Jan 2009

Event-Detecting Multi-Agent Mdps: Complexity And Constant-Factor Approximation, Akshat Kumar, S. Zilberstein

Research Collection School Of Computing and Information Systems

Planning under uncertainty for multiple agents has grown rapidly with the development of formal models such as multi-agent MDPs and decentralized MDPs. But despite their richness, the applicability of these models remains limited due to their computational complexity. We present the class of event-detecting multi-agent MDPs (eMMDPs), designed to detect multiple mobile targets by a team of sensor agents. We show that eMMDPs are NP-Hard and present a scalable 2-approximation algorithm for solving them using matroid theory and constraint optimization. The complexity of the algorithm is linear in the state-space and number of agents, quadratic in the horizon, and exponential …

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Multifactor Productivity And Idea Transmission Channels In The Malaysian Economy, Ester Shen Ai Chan Jan 2009

Multifactor Productivity And Idea Transmission Channels In The Malaysian Economy, Ester Shen Ai Chan

Dissertations and Theses Collection (Open Access)

This paper examines the contribution of multifactor productivity (MFP) growth to output per worker growth in Malaysia from 1961-2000. MFP growth is found to contribute about 74 percent to output per worker growth from 1987-2000, but has only minimal or negative contribution to growth in the earlier years. This paper then attempts to explain why MFP growth has such a large contribution to output per worker growth in the period 1987-2000 by looking at international trade as channel of technology or idea transfer from the G5 countries into Malaysia. MFP grows because ideas from these advanced nations are transferred into …

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Offering Rss Feeds: Does It Help To Gain Competitive Advantage?, Dan Ma Jan 2009

Offering Rss Feeds: Does It Help To Gain Competitive Advantage?, Dan Ma

Research Collection School Of Computing and Information Systems

Nowadays, many Websites have adopted the really simple syndication (RSS) technology to deliver online content to visitors. In this paper, I build an analytical model to examine how the offering of RSS feeds impact the number of visitors, total traffic load, and profit of Websites in a competitive setting. I show that although RSS can always attract more visitors, it may reduce the Website's profit. Interestingly, in a competitive market there are cases that the RSS feeds hurt the offering Website but benefit the competing Website instead. The conditions under which these will happen are derived. I also study the …

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Multiuser Private Queries Over Encrypted Databases, Yanjiang Yang, Feng Bao, Xuhua Ding, Robert H. Deng Jan 2009

Multiuser Private Queries Over Encrypted Databases, Yanjiang Yang, Feng Bao, Xuhua Ding, Robert H. Deng

Research Collection School Of Computing and Information Systems

Searchable encryption schemes allow users to perform keyword-based searches on an encrypted database. Almost all existing such schemes only consider the scenario where a single user acts as both the data owner and the querier. However, most databases in practice do not just serve one user; instead, they support search and write operations by multiple users. In this paper, we systematically study searchable encryption in a practical multiuser setting. Our results include a set of security notions for multiuser searchable encryption as well as a construction which is provably secure under the newly introduced security notions. We also discuss how …

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When Is It Beneficial For A Firm To Pursue A Unified Procurement Strategy For Enterprise Software Solutions?, Robert J. Kauffman, Juliana Y. Tsai Jan 2009

When Is It Beneficial For A Firm To Pursue A Unified Procurement Strategy For Enterprise Software Solutions?, Robert J. Kauffman, Juliana Y. Tsai

Research Collection School Of Computing and Information Systems

The underlying structure of the enterprise software marketplace during the past ten years suggests that the arrangements that firms make with respect to the acquisition of such software capabilities will become increasingly concentrated. This article explores the multiple theoretical rationales and business cases for the move to a unified procurement strategy for enterprise software, reflecting some differences in terms of what might be expected from the predictions of the well known move-to-the-middle hypothesis. Our central argument is that a "move-to-the-middle" with more than just a single vendor is the likely outcome in unconsolidated industry markets. In industries experiencing consolidation, firms …

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A Metaheuristic For The Pickup And Delivery Problem With Split-Loads And Its Extension, Dai Yao Jan 2009

A Metaheuristic For The Pickup And Delivery Problem With Split-Loads And Its Extension, Dai Yao

Dissertations and Theses Collection (Open Access)

In this dissertation, we study improvements in the Pickup and Delivery Problem that can be achieved by allowing multiple vehicle trips to serve a common load. We explore how costs can be reduced through the elimination of the constraint that a load must be served by only one vehicle trip. Specifically, we investigate the problem of routing vehicles to serve loads that have distinct origins and destinations, with no constraint on the amount of a load that a vehicle may serve at a time. We develop a metaheuristic to solve large scale practical size problems in this form and apply …

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The Effect Of Concentrated Institutional Portfolio On Stock Returns, Hao Li Zhang Jan 2009

The Effect Of Concentrated Institutional Portfolio On Stock Returns, Hao Li Zhang

Dissertations and Theses Collection (Open Access)

This paper examines whether stock return is related to the extent of portfolio concentration on the part of institutional fund managers. There is evidence that large firms are preferred for both concentrated and well-diversified funds. Also, a trading strategy based on concentrated ownership generates positive abnormal return. This implies that informational effect (implied in an increase in concentrated capital) has significant impacts and predictability on returns. Meanwhile, we do not find diversified ownership has predictability on future stock returns.

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A Semiotic Analysis Of Unified Modeling Language Graphical Notations, Keng Siau, Yuhong Tian Jan 2009

A Semiotic Analysis Of Unified Modeling Language Graphical Notations, Keng Siau, Yuhong Tian

Research Collection School Of Computing and Information Systems

Unified modeling language (UML) is the standard modeling language for object-oriented system development. Despite its status as a standard, UML has a fuzzy formal specification and a weak theoretical foundation. Semiotics, the study of signs, provides a good theoretical foundation for UML research because graphical notations (or visual signs) of UML are subjected to the principles of signs. In our research, we use semiotics to study the effectiveness of graphical notations in UML. We hypothesized that the use of iconic signs as UML graphical notations leads to representation that is more accurately interpreted and that arouses fewer connotations than the …

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Ontology-Based Business Process Customization For Composite Web Services, Qianhui (Althea) Liang, Xindong Wu, E. K. Park, T. Khoshgoftaar, C. Chi Jan 2009

Ontology-Based Business Process Customization For Composite Web Services, Qianhui (Althea) Liang, Xindong Wu, E. K. Park, T. Khoshgoftaar, C. Chi

Research Collection School Of Computing and Information Systems

A key goal of the Semantic Web is to shift social interaction patterns from a producer-centric paradigm to a consumer-centric one. Treating customers as the most valuable assets and making the business models work better for them are at the core of building successful consumer-centric business models. It follows that customizing business processes constitutes a major concern in the realm of a knowledge-pull-based human semantic Web. This paper conceptualizes the customization of service-based business processes leveraging the existing knowledge of Web services and business processes. We represent this conceptualization as a new Extensible Markup Language (XML) markup language Web Ontology …

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A Comprehensive Study For Rfid Malwares On Mobile Devices, Qiang Yan, Yingjiu Li, Tieyan Li, Robert Huijie Deng Jan 2009

A Comprehensive Study For Rfid Malwares On Mobile Devices, Qiang Yan, Yingjiu Li, Tieyan Li, Robert Huijie Deng

Research Collection School Of Computing and Information Systems

Radio Frequency Identification (RFID) technique has been widely accepted as wireless identification standard in the business world. While RFID technique enables efficient collection of identification information, it also introduces new security risk due to the emerging of RFID malwares. This risk becomes increasingly severe due to the adoption of internet in RFID applications (e.g., track and trace in EPCglobal network) and the use of mobile devices as RFID readers. The prior work to defend the threat of RFID malwares has mainly focused on the protection of front-end tag-reader communications and back-end database systems. Less work has been conducted to defend …

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Quality-Aware Collaborative Question Answering: Methods And Evaluation, Maggy Anastasia Suryanto, Ee Peng Lim, Aixin Sun, Roger Hsiang-Li Chiang Jan 2009

Quality-Aware Collaborative Question Answering: Methods And Evaluation, Maggy Anastasia Suryanto, Ee Peng Lim, Aixin Sun, Roger Hsiang-Li Chiang

Research Collection School Of Computing and Information Systems

Community Question Answering (QA) portals contain questions and answers contributed by hundreds of millions of users. These databases of questions and answers are of great value if they can be used directly to answer questions from any user. In this research, we address this collaborative QA task by drawing knowledge from the crowds in community QA portals such as Yahoo! Answers. Despite their popularity, it is well known that answers in community QA portals have unequal quality. We therefore propose a quality-aware framework to design methods that select answers from a community QA portal considering answer quality in addition to …

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Partially Materialized Digest Scheme: An Efficient Verification Method For Outsourced Databases, Kyriakos Mouratidis, Dimitris Sacharidis, Hwee Hwa Pang Jan 2009

Partially Materialized Digest Scheme: An Efficient Verification Method For Outsourced Databases, Kyriakos Mouratidis, Dimitris Sacharidis, Hwee Hwa Pang

Research Collection School Of Computing and Information Systems

In the outsourced database model, a data owner publishes her database through a third-party server; i.e., the server hosts the data and answers user queries on behalf of the owner. Since the server may not be trusted, or may be compromised, users need a means to verify that answers received are both authentic and complete, i.e., that the returned data have not been tampered with, and that no qualifying results have been omitted. We propose a result verification approach for one-dimensional queries, called Partially Materialized Digest scheme (PMD), that applies to both static and dynamic databases. PMD uses separate indexes …

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The Price Of Stability In Selfish Scheduling Games, Lucas Agussurja, Hoong Chuin Lau Jan 2009

The Price Of Stability In Selfish Scheduling Games, Lucas Agussurja, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Game theory has gained popularity as an approach to analysing and understanding distributed systems with self-interested agents. Central to game theory is the concept of Nash equilibrium as a stable state (solution) of the system, which comes with a price − the loss in efficiency. The quantification of the efficiency loss is one of the main research concerns. In this paper, we study the quality and computational characteristics of the best Nash equilibrium in two selfish scheduling models: the congestion model and the sequencing model. In particular, we present the following results: (1) In the congestion model: first, the best …

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Continuous Monitoring Of Spatial Queries, Kyriakos Mouratidis Jan 2009

Continuous Monitoring Of Spatial Queries, Kyriakos Mouratidis

Research Collection School Of Computing and Information Systems

No abstract provided.

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Efficient Valid Scope Computation For Location-Dependent Spatial Queries In Mobile And Wireless Environments, Ken C. K. Lee, Wang-Chien Lee, Hong Va Leong, Brandon Unger, Baihua Zheng Jan 2009

Efficient Valid Scope Computation For Location-Dependent Spatial Queries In Mobile And Wireless Environments, Ken C. K. Lee, Wang-Chien Lee, Hong Va Leong, Brandon Unger, Baihua Zheng

Research Collection School Of Computing and Information Systems

In mobile and wireless environments, mobile clients can access information with respect to their locations by submitting Location-Dependent Spatial Queries (LDSQs) to Location-Based Service (LBS) servers. Owing to scarce wireless channel bandwidth and limited client battery life, frequent LDSQ submission from clients must be avoided. Observing that LDSQs issued from similar client positions would normally return the same results, we explore the idea of valid scope, that represents a spatial area in which a set of LDSQs will retrieve exactly the same query results. With a valid scope derived and an LDSQ result cached at the client side, a client …

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Signal Detection With Criterion Noise: Applications To Recognition Memory, Aaron S. Benjamin, Michael Diaz, Wee, Serena Jan 2009

Signal Detection With Criterion Noise: Applications To Recognition Memory, Aaron S. Benjamin, Michael Diaz, Wee, Serena

Research Collection School of Social Sciences

A tacit but fundamental assumption of the theory of signal detection is that criterion placement is a noise-free process. This article challenges that assumption on theoretical and empirical grounds and presents the noisy decision theory of signal detection (ND-TSD). Generalized equations for the isosensitivity function and for measures of discrimination incorporating criterion variability are derived, and the model's relationship with extant models of decision making in discrimination tasks is examined, An experiment evaluating recognition memory for ensembles of word stimuli revealed that criterion noise is not trivial in magnitude and contributes substantially to variance in the slope of the isosensitivity …

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Traditions Of Philanthropic Order, Christine Dunn Henderson Jan 2009

Traditions Of Philanthropic Order, Christine Dunn Henderson

Research Collection School of Social Sciences

Individuals act more or less simultaneously as economic agents, citizens, and participants in civil society. Their interactions and their ways of fulfilling these roles take many forms. Not all of them can be said to be self-organizing, yet in several instances patterns of organization emerge spontaneously without being deliberately designed. Of course, the market economy—or “catallaxy,” as F. A. Hayek called it—remains the best example of such “spontaneous orders.” But there are others. Gus diZerega (2000), for example, has identified science and democracy as being similarly constituted by self-referential, self-organizing (some authors prefer the term autopoietic) processes. In this paper …

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If We Seek, Do We Learn?: Predicting Knowledge Of Global Warming, Leeann Kahlor, Sonny Rosenthal Jan 2009

If We Seek, Do We Learn?: Predicting Knowledge Of Global Warming, Leeann Kahlor, Sonny Rosenthal

Research Collection College of Integrative Studies

Derived from the risk information seeking and processing model (RISP), this study sought to isolate predictors of the public's knowledge of global warming. Using a national sample ( N = 805), multiple regression yielded a number of significant relationships among 13 moderators. Notably, the number of media sources used for information about global warming, information seeking effort, and general education were relatively strong predictors of knowledge. Counter to expectations, informational subjective norms were inversely related to knowledge.

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Chaos And Uncertainty, M. Thulasidas Jan 2009

Chaos And Uncertainty, M. Thulasidas

Research Collection School Of Computing and Information Systems

The end of 2008 in the finance industry can be summarized in two words – chaos and uncertainty. The subprime crisis, where everybody lost; the dizzying commodity price movements; the pink slip syndrome; the spectacular bank busts; and the gargantuan bail-outs all vouch for it.

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Distributed Utility-Based Rate Adaptation Protocols For Prioritized, Quasi-Elastic Flows, Sharanya Eswaran, Matthew P. Johnson, Archan Misra, Thomas La Porta Jan 2009

Distributed Utility-Based Rate Adaptation Protocols For Prioritized, Quasi-Elastic Flows, Sharanya Eswaran, Matthew P. Johnson, Archan Misra, Thomas La Porta

Research Collection School Of Computing and Information Systems

This paper considers rate adaptation for streaming multimedia data in a wireless sensor network (WSN) consisting of multiple missions, where each mission subscribes to data streams from multiple sensors, and each sensor's data is utilized by multiple heterogenous missions. We specifically consider the application of the distributed network utility maximization (NUM) framework to a previously unconsidered scenario where the different missions have different priorities, as well as minimum utility demands. When all the utility demands are feasible, we first show that the addition of a penalty for failing to reach the minimum utility demand to the base NUM protocol leads …

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Integrated Resource Allocation And Scheduling In Bidirectional Flow Shop With Multi-Machine And Cos Constraints, Hoong Chuin Lau, Zhengyi Zhao, Shuzhi Sam Ge Jan 2009

Integrated Resource Allocation And Scheduling In Bidirectional Flow Shop With Multi-Machine And Cos Constraints, Hoong Chuin Lau, Zhengyi Zhao, Shuzhi Sam Ge

Research Collection School Of Computing and Information Systems

An integer programming (IP) model is proposed for integrated resource allocation and operation scheduling for a multiple job-agents system. Each agent handles a specific job-list in a bidirectional flowshop. For the individual agent scheduling problem, a formulation is proposed in continuous time domain and compared with an IP formulation in discrete time domain. Of particular interest is the formulation of the machine utilization function-- both in continuous time and discrete time. Fast heuristic methods are proposed with the relaxation of the machine capacity. For the integrated resource allocation and scheduling problem, a linear programming relaxation approach is applied to solve …

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Semiparametric Prevalence Estimation From A Two-Phase Survey, Denis H. Y. Leung, J Qin Jan 2009

Semiparametric Prevalence Estimation From A Two-Phase Survey, Denis H. Y. Leung, J Qin

Research Collection School Of Economics

This paper studies a semi-parametric method for estimating the prevalence of a binary outcome using a two-phase survey. The motivation for a two-phase survey is, due to time, money and ethical considerations, it is impossible to carry out comprehensive evaluation on all subjects in a large random sample of the population. Rather, a relatively inexpensive "screening test" is given to all subjects in the random sample and only individuals more likely to have a positive outcome (cases) will be selected for a further "gold standard" test to verify the outcome. Therefore, individuals with verified outcome form a non-random sample from …

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The Architecture Of Platforms: A Unified View, Carliss Y. Baldwin, C. Jason Woodard Jan 2009

The Architecture Of Platforms: A Unified View, Carliss Y. Baldwin, C. Jason Woodard

Research Collection School Of Computing and Information Systems

Product and system designers have long exploited opportunities to create families of complex artifacts by developing and recombining modular components. An especially common design pattern has come to be associated with the concept of a ‘platform’, which we define as a set of stable components that supports variety and evolvability in a system by constraining the linkages among the other components. Our goal in this chapter is to shed light on the relationships between platforms and the systems in which they are embedded, in order to better understand firms and industries where platforms play an important role. We begin by …

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Modelling Situation Awareness For Context‐Aware Decision Support, Yu-Hong Feng, Teck-Hou Teng, Ah-Hwee Tan Jan 2009

Modelling Situation Awareness For Context‐Aware Decision Support, Yu-Hong Feng, Teck-Hou Teng, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Situation awareness modelling is popularly used in the command and control domain for situation assessment and decision support. However, situation models in real-world applications are typically complex and not easy to use. This paper presents a Context-aware Decision Support (CaDS) system, which consists of a situation model for shared situation awareness modelling and a group of entity agents, one for each individual user, for focused and customized decision support. By incorporating a rule-based inference engine, the entity agents provide functions including event classification, action recommendation, and proactive decision making. The implementation and the performance of the proposed system are demonstrated …

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Web Social Mining, Hady W. Lauw, Ee Peng Lim Jan 2009

Web Social Mining, Hady W. Lauw, Ee Peng Lim

Research Collection School Of Computing and Information Systems

No abstract provided.

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