Search (8 results, page 1 of 1)

  • × author_ss:"Crestani, F."
  1. Crestani, F.; Rijsbergen, C.J. van: Information retrieval by logical imaging (1995) 0.04
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    Abstract
    The evaluation of an implication by imaging is a logical technique developed in the framework of modal logic. Its interpretation in the context of a 'possible worlds' semantics is very appealing for information retrieval. In 19889, Van Rijsbergen suggested its use for solving 1 of the fundamental problems of logical models of information retrieval: the evaluation of the logical implication that a document is relevant to a query if it implies the query. Since then, others have tried to follow that suggestion proposing models and applications, though without much success. Most of these approaches had as their basic assunption the consideration that ' document is a possible world'. Proposes instead an approach based on a completely different assumption: ' a term is a possible world'. This approach enables the exploitation of term-term relationships which are estimated using an information theoretic measure
  2. Tombros, T.; Crestani, F.: Users' perception of relevance of spoken documents (2000) 0.04
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    Abstract
    We present the results of a study of user's perception of relevance of documents. The aim is to study experimentally how users' perception varies depending on the form that retrieved documents are presented. Documents retrieved in response to a query are presented to users in a variety of ways, from full text to a machine spoken query-biased automatically-generated summary, and the difference in users' perception of relevance is studied. The experimental results suggest that the effectiveness of advanced multimedia Information Retrieval applications may be affected by the low level of users' perception of relevance of retrieved documents
  3. Crestani, F.; Vegas, J.; Fuente, P. de la: ¬A graphical user interface for the retrieval of hierarchically structured documents (2004) 0.03
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    Abstract
    Past research has proved that graphical user interfaces (GUIs) can significantly improve the effectiveness of the information access task. Our work is based on the consideration that structured document retrieval requires different user graphical interfaces from standard information retrieval. In structured document retrieval a GUI has to enable a user to query, browse retrieved documents, provide query refinement and relevance feedback based not only on full documents, but also on specific document parts in relation to the document structure. In this paper, we present a new GUI for structured document retrieval specifically designed for hierarchically structured documents. A user task-oriented evaluation has shown that the proposed interface provides the user with an intuitive and powerful set of tools for structured document searching, retrieved list navigation, and search refinement.
  4. Crestani, F.; Wu, S.: Testing the cluster hypothesis in distributed information retrieval (2006) 0.03
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    Abstract
    How to merge and organise query results retrieved from different resources is one of the key issues in distributed information retrieval. Some previous research and experiments suggest that cluster-based document browsing is more effective than a single merged list. Cluster-based retrieval results presentation is based on the cluster hypothesis, which states that documents that cluster together have a similar relevance to a given query. However, while this hypothesis has been demonstrated to hold in classical information retrieval environments, it has never been fully tested in heterogeneous distributed information retrieval environments. Heterogeneous document representations, the presence of document duplicates, and disparate qualities of retrieval results, are major features of an heterogeneous distributed information retrieval environment that might disrupt the effectiveness of the cluster hypothesis. In this paper we report on an experimental investigation into the validity and effectiveness of the cluster hypothesis in highly heterogeneous distributed information retrieval environments. The results show that although clustering is affected by different retrieval results representations and quality, the cluster hypothesis still holds and that generating hierarchical clusters in highly heterogeneous distributed information retrieval environments is still a very effective way of presenting retrieval results to users.
  5. Keikha, M.; Crestani, F.; Carman, M.J.: Employing document dependency in blog search (2012) 0.02
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    Abstract
    The goal in blog search is to rank blogs according to their recurrent relevance to the topic of the query. State-of-the-art approaches view it as an expert search or resource selection problem. We investigate the effect of content-based similarity between posts on the performance of the retrieval system. We test two different approaches for smoothing (regularizing) relevance scores of posts based on their dependencies. In the first approach, we smooth term distributions describing posts by performing a random walk over a document-term graph in which similar posts are highly connected. In the second, we directly smooth scores for posts using a regularization framework that aims to minimize the discrepancy between scores for similar documents. We then extend these approaches to consider the time interval between the posts in smoothing the scores. The idea is that if two posts are temporally close, then they are good sources for smoothing each other's relevance scores. We compare these methods with the state-of-the-art approaches in blog search that employ Language Modeling-based resource selection algorithms and fusion-based methods for aggregating post relevance scores. We show performance gains over the baseline techniques which do not take advantage of the relation between posts for smoothing relevance estimates.
  6. Crestani, F.; Rijsbergen, C.J. van: Information retrieval by imaging (1996) 0.01
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    Source
    Information retrieval: new systems and current research. Proceedings of the 16th Research Colloquium of the British Computer Society Information Retrieval Specialist Group, Drymen, Scotland, 22-23 Mar 94. Ed.: R. Leon
  7. Crestani, F.; Dominich, S.; Lalmas, M.; Rijsbergen, C.J.K. van: Mathematical, logical, and formal methods in information retrieval : an introduction to the special issue (2003) 0.01
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    Date
    22. 3.2003 19:27:36
  8. Crestani, F.; Du, H.: Written versus spoken queries : a qualitative and quantitative comparative analysis (2006) 0.01
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    Date
    5. 6.2006 11:22:23