3 research outputs found

    Web Page Enrichment using a Rough Set Based Method

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    When documents are matched to a given query, often the terms in the query are matched to the words in the documents for calculating similarity. But it is a good idea if the given document is represented in an enriched manner with not only the actual words occurring in the document but also with the synonyms of the important words. This would definitely improve the recall of the system. With its ability to deal with vagueness and fuzziness, tolerance rough set seems to be promising tool to model relations between terms and documents. In many information retrieval problems, especially in text classification, determining the relation between term-term and term-document is essential. In this work, the application of TRSM to web page classification was evaluated to determine its effectiveness as a way to enrich a web page

    Towards the Semantic Text Retrieval for Indonesian

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    Indonesia is the fourth most populous country in the world and the Asosiasi Penyelenggara Jasa Internet Indonesia (Indonesian Internet Service Providers Association) recorded that Indonesian Internet subscribers and users has been growing rapidly every year. These facts should encourage research such as computer linguistic and information retrieval for Indonesian language which in fact has not been extensively investigated. The research aims to investigate the tolerance rough sets model (TRSM) in order to propose a framework for a semantic text retrieval system. The proposed framework is intended for Indonesian language specifically hence we are working with Indonesian corpora and applying tools for Indonesian, e.g. Indonesian stemmer, in all of the studies. Cognitive approach is employed particularly during data preparation and analysis. An extensive collaboration with human experts is significant on creating a new Indonesian corpus suitable for our research. The performance of an ad hoc retrieval system becomes the starting point for further analysis in order to learn and understand more about the process and characteristic of TRSM, despite comparing TRSM with other methods and determining the best solution. The results of this process function as the guidance for computational modeling of some TRSM's tasks and finally the framework of a semantic information retrieval system with TRSM as its heart. In addition to the proposed framework, this thesis proposes three methods based on TRSM, which are the automatic tolerance value generator, thesaurus optimization, and lexicon-based document representation. All methods were developed by the use of our own corpus, namely ICL-corpus, and evaluated by employing an available Indonesian corpus, called Kompas-corpus. The evaluation on the methods achieved satisfactory results, except for the compact document representation method; this last method seems to work only in limited domain

    Pharmacovigilance Decision Support : The value of Disproportionality Analysis Signal Detection Methods, the development and testing of Covariability Techniques, and the importance of Ontology

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    The cost of adverse drug reactions to society in the form of deaths, chronic illness, foetal malformation, and many other effects is quite significant. For example, in the United States of America, adverse reactions to prescribed drugs is around the fourth leading cause of death. The reporting of adverse drug reactions is spontaneous and voluntary in Australia. Many methods that have been used for the analysis of adverse drug reaction data, mostly using a statistical approach as a basis for clinical analysis in drug safety surveillance decision support. This thesis examines new approaches that may be used in the analysis of drug safety data. These methods differ significantly from the statistical methods in that they utilize co variability methods of association to define drug-reaction relationships. Co variability algorithms were developed in collaboration with Musa Mammadov to discover drugs associated with adverse reactions and possible drug-drug interactions. This method uses the system organ class (SOC) classification in the Australian Adverse Drug Reaction Advisory Committee (ADRAC) data to stratify reactions. The text categorization algorithm BoosTexter was found to work with the same drug safety data and its performance and modus operandi was compared to our algorithms. These alternative methods were compared to a standard disproportionality analysis methods for signal detection in drug safety data including the Bayesean mulit-item gamma Poisson shrinker (MGPS), which was found to have a problem with similar reaction terms in a report and innocent by-stander drugs. A classification of drug terms was made using the anatomical-therapeutic-chemical classification (ATC) codes. This reduced the number of drug variables from 5081 drug terms to 14 main drug classes. The ATC classification is structured into a hierarchy of five levels. Exploitation of the ATC hierarchy allows the drug safety data to be stratified in such a way as to make them accessible to powerful existing tools. A data mining method that uses association rules, which groups them on the basis of content, was used as a basis for applying the ATC and SOC ontologies to ADRAC data. This allows different views of these associations (even very rare ones). A signal detection method was developed using these association rules, which also incorporates critical reaction terms.Doctor of Philosoph
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