Information Quality Criteria Analysis in Query Reformulation in Dynamic Distributed Environments

• Ano de defesa: 2013
• Autor(a) principal: SOUZA, Bruno Felipe de França
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Pernambuco
• Palavras-chave em Português: Query Reformulation; Information Quality; PDMS; Distributed Dynamic Environment; Semantic Correspondences; Reformulação de Consultas; Qualidade da Informação; Ambiente Dinâmico e Distribuído; Correspondências Semânticas
• Link de acesso: https://repositorio.ufpe.br/handle/123456789/11611

Dynamic distributed environments are decentralized systems that provide users with querying capabilities over a set of heterogeneous, distributed and autonomous data sources (peers). Data Integration Systems, Peer Data Management Systems (PDMS) and Dataspaces are examples of such systems. They are composed by peers that belong to a specific domain and are linked to each other by correspondences (semantic connections). Nonetheless, a challenge inherent to dynamic distributed environments is the query reformulation process between a pair of peers. When a user poses a query at a peer, in order to acquire more information, the query should be reformulated in accordance with the neighbor peers schema. In this process some problems as semantic loss and query degradation can arise. The semantic loss and query degradation are problems related to the loss of semantic concepts during query reformulation. In the other hand, in such a semantic environment instead of a semantic loss the query can have a semantic enrichment by aggregating semantic related concepts during reformulation. In this sense, the user’s query can be enriched and semantically richer results can be delivered. Information Quality criteria has been used in some works to evaluate the level of quality of the distributed dynamic environment’s elements such as, peers, data and query answer. These criteria are dynamic measures provided by the system and serve as scores that can be constantly evaluated to get the actual level of quality. In this work we present four Information Quality criteria that measure the loss and enrichment of semantic concepts during query reformulation among peers. We present an example of our analysis and the algorithms that implement the evaluation of the presented criteria. We also give our definitions to the semantic loss and query degradation problems. Finally, we present the experimentation we have done with the SPEED PDMS and the obtained results.