Contributions to fuzzy object comparison and applications. Similarity measures for fuzzy and heterogeneous data and their applications.
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Publication date
2014-05-02Supervisor
Neagu, DanielRidley, Mick J.
Keyword
Similarity MeasuresFuzzy Geometrical Similarity Model
Fuzzy Set-Theoretical Similarity Model
Fuzzy objects
Heterogeneous data
Fuzzy attributes
Numerical attributes
Categorical attributes
Data objects
Comparison
Rights
The University of Bradford theses are licenced under a Creative Commons Licence.
Institution
University of BradfordDepartment
Department of Computing, School of Computing, Informatics and MediaAwarded
2013Metadata
Show full item recordAbstract
This thesis makes an original contribution to knowledge in the fi eld of data objects' comparison where the objects are described by attributes of fuzzy or heterogeneous (numeric and symbolic) data types. Many real world database systems and applications require information management components that provide support for managing such imperfect and heterogeneous data objects. For example, with new online information made available from various sources, in semi-structured, structured or unstructured representations, new information usage and search algorithms must consider where such data collections may contain objects/records with di fferent types of data: fuzzy, numerical and categorical for the same attributes. New approaches of similarity have been presented in this research to support such data comparison. A generalisation of both geometric and set theoretical similarity models has enabled propose new similarity measures presented in this thesis, to handle the vagueness (fuzzy data type) within data objects. A framework of new and unif ied similarity measures for comparing heterogeneous objects described by numerical, categorical and fuzzy attributes has also been introduced. Examples are used to illustrate, compare and discuss the applications and e fficiency of the proposed approaches to heterogeneous data comparison.Type
ThesisQualification name
PhDCollections
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