Fuzzy Proximity Ranking with Boolean Queries

http://trec.nist.gov/pubs/trec14/papers/ecole-des-mines.pdfInternational audienceBased on the idea that the closer the query terms are in a document, the more relevant this document is, we experiment an IR method based on a fuzzy proximity degree of the query term occurences in a document to compute its relevance to the query. Our model is able to deal with Boolean queries, but contrary to the traditional extensions of the basic Boolean IR model, it does not explicitly use a proximity operator. The fuzzy term proximity is controlled with an in uence function. Given a query term and a document, the in uence function associates to each position in the text a value dependant on the distance of the nearest occurence of this query term. To model proximity, this function is decreasing with distance. Di erent forms of function can be used: triangular, gaussian etc. For practical reasons only functions with nite support were used. The support of the function is limited by a constant called k. The fuzzy term proximity functions are associated to every leaves of the query tree. Then fuzzy proximities are computed for every nodes with a post-order tree traversal. Given the fuzzy proximities of the sons of a node, its fuzzy proximity is computed, like in the fuzzy IR models, with a mimimum (resp. maximum) combination for conjunctives (resp. disjunctives) nodes. Finally, a fuzzy query proximity value is obtained for each position in this document at the root of the query tree. The score of this document is the integration of the function obtained at the tree root. For the experiments, we modi ed Lucy (version 0.5.2) to implement our IR model. Three query sets are used for our eight runs. One set is manually built with the title words and some description words. Each of these words is OR'ed with its derivatives like plurals for instance. Then the OR nodes obtained are AND'ed at the tree root. The two automatic query sets are built with an AND of automatically extracted terms from either the title eld or the description eld. These three query sets are submitted to our system with two values of k: 50 and 200. As our method is aimed at high precision, it sometimes give less than one thousand answers. In such cases, the documents retrieved by the BM-25 method implemented in Lucy was concatenated after our result list

Agente para recuperación automática de información en diversos entornos basado en técnicas de inteligencia computacional

Falta palabras clavesLa presente tesis se enmarca en la problemática de la recuperación de información, entendiendo por recuperación de información la búsqueda dentro de una colección de documentos diversos, de forma automática, de todos los documentos relacionados, con un cierto grado de relevancia, a partir de una consulta formulada por un usuario. En particular, expone un novedoso sistema, basado en lógica difusa, para la implementación de agentes inteligentes para resolver problemas reales de recuperación de información en diversos entornos. Los métodos de recuperación de información y de asignación de pesos desarrollados dan lugar a las publicaciones que se adjuntan en el compendio de esta tesis; y su aplicación propicia una entrada en la oficina de registro de la propiedad intelectual. En los trabajos de colaboración con empresa relacionados en el Capítulo 5 se han implementado diversos prototipos de agentes inteligentes aplicando las técnicas de inteligencia computacional que sustentan los métodos de recuperación de información desarrollados, con la finalidad de crear agentes inteligentes para resolución de problemas reales en los que se necesita realizar una recuperación de información. Los agentes inteligentes desarrollados utilizan el método de recuperación de información, el método de asignación de pesos, y la estructura de almacenamiento de información desarrollada en las publicaciones que forman el compendio de esta tesis. En dichas publicaciones se justifica el buen funcionamiento de estos métodos, así como la mejora de rendimiento en la recuperación de información contenida en portales web frente al modelo de espacio vectorial (Vector Space Model, VSM) y el método de asignación de pesos tf-idf

Fuzzy Proximity Ranking with Boolean Queries

Based on the idea that the closer the query terms are in a document, the more relevant this document is, we experiment an IR method based on a fuzzy proximity degree of the query term occurences in a document to compute its relevance to the query. Our model is able to deal with Boolean queries, but contrary to the traditional extensions of the basic Boolean IR model, it does not explicitly use a proximity operator. The fuzzy term proximity is controlled with an influence function. Given a query term and a document, the influence function associates to each position in the text a value dependant on the distance of the nearest occurence of this query term. To model proximity, this function is decreasing with distance. Di#erent forms of function can be used: triangular, gaussian etc. For practical reasons only functions with finite support were used. The support of the function is limited by a constant called k. The fuzzy term proximity functions are associated to every leaves of the query tree. Then fuzzy proximities are computed for every nodes with a post-order tree traversal. Given the fuzzy proximities of the sons of a node, its fuzzy proximity is computed, like in the fuzzy IR models, with a mimimum (resp. maximum) combination for conjunctives (resp. disjunctives) nodes. Finally, a fuzzy query proximity value is obtained for each position in this document at the root of the query tree. The score of this document is the integration of the function obtained at the tree root. For the experiments, we modified Lucy (version 0.5.2) to implement our IR model. Three query sets are used for our eight runs. One set is manually built with the title words and some description words. Each of these words is OR'ed with its derivatives like plurals for instance. Then the OR nodes ob..