Using the pagerank algorithm to explore a physician referral network

Dissertation presented as the partial requirement for obtaining a Master's degree in Data Science and Advanced AnalyticsPageRank algorithm is nowadays the baseline in search engine being the tool behind Google’s operation. However, since it was defined many different approaches have been tried in different knowledge areas. In this document a description of this tool, specification of the different areas where it has been used and new application of this algorithm in a physician referral network are presented

GENERIC FRAMEWORKS FOR INTERACTIVE PERSONALIZED INTERESTING PATTERN DISCOVERY

The traditional frequent pattern mining algorithms generate an exponentially large number of patterns of which a substantial portion are not much significant for many data analysis endeavours. Due to this, the discovery of a small number of interesting patterns from the exponentially large number of frequent patterns according to a particular user\u27s interest is an important task. Existing works on patter

The retail market as a complex system

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Intercultural exchanges in a foreign language dimension in retrospect: a corpus analysis of respondents' perceptions

This paper aims at reassessing some evidence on EFL learners’/undergraduates’ perceptions on intercultural exchanges in/between a foreign language (FL) and mother tongue (L1), grounded on an empirical research undertaken in Madeira (1998-1999). This involved a representative number of 12th form Humanities students (secondary school) and first- and second-year undergraduates taking English (Joint Honours) then. The process of interpretation of respondents’ output borrows from a cross-disciplinary framework (Traugott and Pratt 1980, Woods et al. 1996) in a postmodern paradigm of applied research to which Foucault (1972), Bakhtin ([1935] 1990) and Barthes (1975) have left their contribution, while resorting to corpus analysis (Biber et al. 1998, Sinclair 2004). The analysis of some core lexemes, like text, knowledge, and meaning, and other collocations were singled out which have allowed for the identification of recurrent patterns (for example, “informative texts”, “descriptive texts” and “cultural texts”) and the meaning potential associated with them. Among the issues under scrutiny, there will be a focus on both language/culture interface underpinning FL teaching/learning standards, and informants’ affective identification with a foreign language/culture reinforced by the so-called representative cultural artefacts (Byram 1988: 41). In the discussion about the dialogic encounter of mother tongue/foreign languages, issues of culture, identity, discursive communities and practices will come to the fore.info:eu-repo/semantics/publishedVersio

The Archivist’s New Clothes; or, the Naked Truth about Evidence, Transactions, and Recordness

The electronic records projects at the University of British Columbia (UBC) and the University of Pittsburgh (Pitt) have been promoted as competing visions of the archival future. This article, the work of several authors with experience as both manuscript curators and institutional archivists, challenges the perception that the UBC and Pitt models are fundamentally different from one another, and argues that they share a similar and deeply flawed conception of the meaning of archives and the mission of the archival profession. Rather than accept the premises upon which both UBC and Pitt build their models, archivists should re-assert the broader and more practical theory of archives that has dominated much of U.S. archival history

Efficient Mining Support-Confidence Based Framework Generalized Association Rules

Mining association rules are one of the most critical data mining problems, intensively studied since their inception. Several approaches have been proposed in the literature to extend the basic association rule framework to extract more general rules, including the negation operator. Thereby, this extension is expected to bring valuable knowledge about an examined dataset to the user. However, the efficient extraction of such rules is challenging, especially for sparse datasets. This paper focuses on the extraction of literalsets, i.e., a set of present and absent items. By consequence, generalized association rules can be straightforwardly derived from these literalsets. To this end, we introduce and prove the soundness of a theorem that paves the way to speed up the costly computation of the support of a literalist. Furthermore, we introduce FasterIE, an efficient algorithm that puts the proved theorem at work to efficiently extract the whole set of frequent literalets. Thus, the FasterIE algorithm is shown to devise very efficient strategies, which minimize as far as possible the number of node visits in the explored search space. Finally, we have carried out experiments on benchmark datasets to back the effectiveness claim of the proposed algorithm versus its competitors

Tracing the Compositional Process. Sound art that rewrites its own past: formation, praxis and a computer framework

The domain of this thesis is electroacoustic computer-based music and sound art. It investigates a facet of composition which is often neglected or ill-defined: the process of composing itself and its embedding in time. Previous research mostly focused on instrumental composition or, when electronic music was included, the computer was treated as a tool which would eventually be subtracted from the equation. The aim was either to explain a resultant piece of music by reconstructing the intention of the composer, or to explain human creativity by building a model of the mind. Our aim instead is to understand composition as an irreducible unfolding of material traces which takes place in its own temporality. This understanding is formalised as a software framework that traces creation time as a version graph of transactions. The instantiation and manipulation of any musical structure implemented within this framework is thereby automatically stored in a database. Not only can it be queried ex post by an external researcher—providing a new quality for the empirical analysis of the activity of composing—but it is an integral part of the composition environment. Therefore it can recursively become a source for the ongoing composition and introduce new ways of aesthetic expression. The framework aims to unify creation and performance time, fixed and generative composition, human and algorithmic “writing”, a writing that includes indeterminate elements which condense as concurrent vertices in the version graph. The second major contribution is a critical epistemological discourse on the question of ob- servability and the function of observation. Our goal is to explore a new direction of artistic research which is characterised by a mixed methodology of theoretical writing, technological development and artistic practice. The form of the thesis is an exercise in becoming process-like itself, wherein the epistemic thing is generated by translating the gaps between these three levels. This is my idea of the new aesthetics: That through the operation of a re-entry one may establish a sort of process “form”, yielding works which go beyond a categorical either “sound-in-itself” or “conceptualism”. Exemplary processes are revealed by deconstructing a series of existing pieces, as well as through the successful application of the new framework in the creation of new pieces

Detecting hierarchical relationships and roles from online interaction networks

In social networks, analysing the explicit interactions among users can help in inferring hierarchical relationships and roles that may be implicit. In this thesis, we focus on two objectives: detecting hierarchical relationships between users and inferring the hierarchical roles of users interacting via the same online communication medium. In both cases, we show that considering the temporal dimension of interaction substantially improves the detection of relationships and roles. The first focus of this thesis is on the problem of inferring implicit relationships from interactions between users. Based on promising results obtained by standard link-analysis methods such as PageRank and Rooted-PageRank (RPR), we introduce three novel time-based approaches, \Time-F" based on a defined time function, Filter and Refine (FiRe) which is a hybrid approach based on RPR and Time-F, and Time-sensitive Rooted-PageRank (T-RPR) which applies RPR in a way that takes into account the time-dimension of interactions in the process of detecting hierarchical ties. We experiment on two datasets, the Enron email dataset to infer managersubordinate relationships from email exchanges, and a scientific publication coauthorship dataset to detect PhD advisor-advisee relationships from paper co-authorships. Our experiments demonstrate that time-based methods perform better in terms of recall. In particular T-RPR turns out to be superior over most recent competitor methods as well as all other approaches we propose. The second focus of this thesis is examining the online communication behaviour of users working on the same activity in order to identify the different hierarchical roles played by the users. We propose two approaches. In the first approach, supervised learning is used to train different classification algorithms. In the second approach, we address the problem as a sequence classification problem. A novel sequence classification framework is defined that generates time-dependent features based on frequent patterns at multiple levels of time granularity. Our framework is a exible technique for sequence classification to be applied in different domains. We experiment on an educational dataset collected from an asynchronous communication tool used by students to accomplish an underlying group project. Our experimental findings show that the first supervised approach achieves the best mapping of students to their roles when the individual attributes of the students, information about the reply relationships among them as well as quantitative time-based features are considered. Similarly, our multi-granularity pattern-based framework shows competitive performance in detecting the students' roles. Both approaches are significantly better than the baselines considered

Supply Chains and Porous Boundaries: The Disaggregation of Legal Services

The economic downturn has had significant effects on law firms, and is causing many of them to rethink some basic assumptions about how they operate. In important respects, however, the downturn has simply intensified the effects of some deeper trends that preceded it, which are likely to continue after any recovery that may occur. This paper explores one of these trends, which is corporate client insistence that law firms “disaggregate” their services into discrete tasks that can be delegated to the least costly providers who can perform them. With advances in communications technology, there is increasing likelihood that some of these persons may be located outside the formal boundaries of the firm. This means that law firms may need increasingly to confront the make or buy decision that their corporate clients have regularly confronted for some time. The potential for vertical disintegration is a relatively recent development for legal services, but is well-established in other sectors of the global economy. Empirical work in several disciplines has identified a number of issues that arise for organizations as the make or buy decision becomes a potentially more salient feature of their operations. Much of this work has focused in particular on the implications of relying on outsourcing as an integral part of the production process. This paper discusses research on: (1) the challenges of ensuring that work performed outside the firm is fully integrated into the production process; (2) coordinating projects for which networks of organizations are responsible; (3) managing the transfer of knowledge inside and outside of firms that are participants in a supply chain; and (4) addressing the impact of using contingent workers on an organization’s workforce, structure, and culture. A review of this research suggests considerations that law firms will need to assess if they begin significantly to extend the process of providing services beyond their formal boundaries. Discussing the research also is intended to introduce concepts that may become increasingly relevant to law firms, but which currently are not commonly used to analyze their operations. Considering how these concepts are applicable to law firms may prompt us to rethink how to conceptualize these firms and what they do. This paper therefore is a preliminary attempt to explore: (1) the extent to which law firms may come to resemble the vertically disintegrated organizations that populate many other economic sectors and (2) the potential implications of this trend for the provision of legal services,the trajectory of legal careers, and lawyers’ sense of themselves as members of a distinct profession