Abstract Dynamic pruning strategies for information retrieval systems can increase querying effic... more Abstract Dynamic pruning strategies for information retrieval systems can increase querying efficiency without decreasing effectiveness by using upper bounds to safely omit scoring documents that are unlikely to make the final retrieved set. Often, such upper bounds are pre-calculated at indexing time for a given weighting model. However, this precludes changing, adapting or training the weighting model without recalculating the upper bounds.
Systematic reviews are instances of a critically important search task in medicine and health ser... more Systematic reviews are instances of a critically important search task in medicine and health services research. Along with large and well conducted randomised control trials, they provide the highest levels of clinical evidence. We provide a brief overview of the methodologies used to conduct systematic reviews, and report on our recent experience of conducting a meta-review–ie a systematic review of reviews–of preoperative assessment.
Abstract In information retrieval, the way in which the correspondence procedure works is highly ... more Abstract In information retrieval, the way in which the correspondence procedure works is highly important for the performance of the underlying system as a whole. An inverted file ensures quick access to the information items because the index alone is examined, rather than the actual file of items, in order to determine the items which satisfy a search request. This technique was a prominent feature of the old commercial information retrieval systems (IRSs). However it has been used only for keyword-based IRSs.
Abstract The influential Text REtrieval Conference (TREC) retrieval conference has always relied ... more Abstract The influential Text REtrieval Conference (TREC) retrieval conference has always relied upon specialist assessors or occasionally participating groups to create relevance judgements for the tracks that it runs. Recently however, crowdsourcing has been championed as a cheap, fast and effective alternative to traditional TREC-like assessments. In 2010, TREC tracks experimented with crowdsourcing for the very first time.
This book constitutes the refereed proceedings of the 30th annual European Conference on Informat... more This book constitutes the refereed proceedings of the 30th annual European Conference on Information Retrieval Research, ECIR 2008, held in Glasgow, UK, in March/April 2008. The 33 revised full papers and 19 revised short papers presented together with the abstracts of 3 invited lectures and 32 poster papers were carefully reviewed and selected from 139 full article submissions.
Experimental evidence accumulated over the past years indicated the importance of the ranking pro... more Experimental evidence accumulated over the past years indicated the importance of the ranking process in information retrieval. As for the textual documents, image ranking is a task that involves different parameters. They depend on the intrinsic characteristics of an image, but also on the indexing language used for representing its semantic content. We developed a weighting model that combines these parameters in a general scheme. Finding the best balance between the parameters is not straight-forward.
Abstract This talk will describe the Terrier Information Retrieval Platform, aimed at facilitatin... more Abstract This talk will describe the Terrier Information Retrieval Platform, aimed at facilitating research and experimentation with large textual corpora. In particular, the talk will cover Terrier's most recent developments for supporting large-scale indexing using the MapReduce distributed framework. Additionally, it will also describe our latest efforts towards enabling retrieval in non-English languages (in particular, Asian languages), which will be a core component of the upcoming release of the platform.
Seleccionar todos Título: Monografía. Búsqueda en la Web del futuro. Líneas de investigación en T... more Seleccionar todos Título: Monografía. Búsqueda en la Web del futuro. Líneas de investigación en Terrier: un motor de búsqueda para la recuperación avanzada en la Web. Autores: Ounis, Iadh; Lioma, Christina; Macdonald, Craig; Plachouras, Vassilis.
Browsing is an important but often inefficient information seeking strategy in information retrie... more Browsing is an important but often inefficient information seeking strategy in information retrieval (IR). In this paper, we argue that an effective recommendation model can improve the user's browsing experience. We propose to adapt the intertemporal choice model to model the browsing behaviour of the user. The model can be used to recommend a browsing path to the users. The proposed model is based on the assumption that the browsing recommendation problem is an intertemporal choice problem.
Abstract On the Web, content farms produce articles engineered such that search engines rank them... more Abstract On the Web, content farms produce articles engineered such that search engines rank them highly, in order to turn a profit from online advertising. Recently, content farms have increasingly been the target of demotion strategies by Web search engines, since content farm articles are often considered to be of suspect quality. In this paper, we study the prevalence of content farms in the results returned by three major Web search engines over time.
Abstract. Document fields, such as the title or the headings of a document, offer a way to consid... more Abstract. Document fields, such as the title or the headings of a document, offer a way to consider the structure of documents for retrieval. Most of the proposed approaches in the literature employ either a linear combination of scores assigned to different fields, or a linear combination of frequencies in the term frequency normalisation component. In the context of the Divergence From Randomness framework, we have a sound opportunity to integrate document fields in the probabilistic randomness model.
Abstract We present an alternative technique for discovering aggregate usage profiles from Web ac... more Abstract We present an alternative technique for discovering aggregate usage profiles from Web access logs. The technique is based on clustering information needs inferred from users' browsing paths. Browsing paths are extracted from users' access logs. Information need is inferred from each browsing path by using the Ostensive Model [1]. The technique is evaluated in a document recommendation application.
Expressive indexing languages are called for to obtain faithful representations of multimedia doc... more Expressive indexing languages are called for to obtain faithful representations of multimedia documents. They become a decisive factor to alleviate the noise problem, which is now often encountered with commercial search engines. In this case, noise consists in a great number of non-relevant answers to user's queries, which compromises interrogation efficiency. The use of complex formalisms to handle the problem is not straight-forward, as one of their general characteristics is to have high, sometimes unacceptable computational costs.
Abstract Conceptual graphs can be used as a simple and expressive language for indexing and retri... more Abstract Conceptual graphs can be used as a simple and expressive language for indexing and retrieving non-textual documents. In this knowledge representation formalism, the implementation of the matching function between a query and a document is obtained by the so-called projection operator between two conceptual graphs. A good implementation of the projection algorithm is therefore crucial for managing large bases of text and image documents. We present a new promising implementation.
Abstract Dynamic pruning strategies for information retrieval systems can increase querying effic... more Abstract Dynamic pruning strategies for information retrieval systems can increase querying efficiency without decreasing effectiveness by using upper bounds to safely omit scoring documents that are unlikely to make the final retrieved set. Often, such upper bounds are pre-calculated at indexing time for a given weighting model. However, this precludes changing, adapting or training the weighting model without recalculating the upper bounds.
Systematic reviews are instances of a critically important search task in medicine and health ser... more Systematic reviews are instances of a critically important search task in medicine and health services research. Along with large and well conducted randomised control trials, they provide the highest levels of clinical evidence. We provide a brief overview of the methodologies used to conduct systematic reviews, and report on our recent experience of conducting a meta-review–ie a systematic review of reviews–of preoperative assessment.
Abstract In information retrieval, the way in which the correspondence procedure works is highly ... more Abstract In information retrieval, the way in which the correspondence procedure works is highly important for the performance of the underlying system as a whole. An inverted file ensures quick access to the information items because the index alone is examined, rather than the actual file of items, in order to determine the items which satisfy a search request. This technique was a prominent feature of the old commercial information retrieval systems (IRSs). However it has been used only for keyword-based IRSs.
Abstract The influential Text REtrieval Conference (TREC) retrieval conference has always relied ... more Abstract The influential Text REtrieval Conference (TREC) retrieval conference has always relied upon specialist assessors or occasionally participating groups to create relevance judgements for the tracks that it runs. Recently however, crowdsourcing has been championed as a cheap, fast and effective alternative to traditional TREC-like assessments. In 2010, TREC tracks experimented with crowdsourcing for the very first time.
This book constitutes the refereed proceedings of the 30th annual European Conference on Informat... more This book constitutes the refereed proceedings of the 30th annual European Conference on Information Retrieval Research, ECIR 2008, held in Glasgow, UK, in March/April 2008. The 33 revised full papers and 19 revised short papers presented together with the abstracts of 3 invited lectures and 32 poster papers were carefully reviewed and selected from 139 full article submissions.
Experimental evidence accumulated over the past years indicated the importance of the ranking pro... more Experimental evidence accumulated over the past years indicated the importance of the ranking process in information retrieval. As for the textual documents, image ranking is a task that involves different parameters. They depend on the intrinsic characteristics of an image, but also on the indexing language used for representing its semantic content. We developed a weighting model that combines these parameters in a general scheme. Finding the best balance between the parameters is not straight-forward.
Abstract This talk will describe the Terrier Information Retrieval Platform, aimed at facilitatin... more Abstract This talk will describe the Terrier Information Retrieval Platform, aimed at facilitating research and experimentation with large textual corpora. In particular, the talk will cover Terrier's most recent developments for supporting large-scale indexing using the MapReduce distributed framework. Additionally, it will also describe our latest efforts towards enabling retrieval in non-English languages (in particular, Asian languages), which will be a core component of the upcoming release of the platform.
Seleccionar todos Título: Monografía. Búsqueda en la Web del futuro. Líneas de investigación en T... more Seleccionar todos Título: Monografía. Búsqueda en la Web del futuro. Líneas de investigación en Terrier: un motor de búsqueda para la recuperación avanzada en la Web. Autores: Ounis, Iadh; Lioma, Christina; Macdonald, Craig; Plachouras, Vassilis.
Browsing is an important but often inefficient information seeking strategy in information retrie... more Browsing is an important but often inefficient information seeking strategy in information retrieval (IR). In this paper, we argue that an effective recommendation model can improve the user's browsing experience. We propose to adapt the intertemporal choice model to model the browsing behaviour of the user. The model can be used to recommend a browsing path to the users. The proposed model is based on the assumption that the browsing recommendation problem is an intertemporal choice problem.
Abstract On the Web, content farms produce articles engineered such that search engines rank them... more Abstract On the Web, content farms produce articles engineered such that search engines rank them highly, in order to turn a profit from online advertising. Recently, content farms have increasingly been the target of demotion strategies by Web search engines, since content farm articles are often considered to be of suspect quality. In this paper, we study the prevalence of content farms in the results returned by three major Web search engines over time.
Abstract. Document fields, such as the title or the headings of a document, offer a way to consid... more Abstract. Document fields, such as the title or the headings of a document, offer a way to consider the structure of documents for retrieval. Most of the proposed approaches in the literature employ either a linear combination of scores assigned to different fields, or a linear combination of frequencies in the term frequency normalisation component. In the context of the Divergence From Randomness framework, we have a sound opportunity to integrate document fields in the probabilistic randomness model.
Abstract We present an alternative technique for discovering aggregate usage profiles from Web ac... more Abstract We present an alternative technique for discovering aggregate usage profiles from Web access logs. The technique is based on clustering information needs inferred from users' browsing paths. Browsing paths are extracted from users' access logs. Information need is inferred from each browsing path by using the Ostensive Model [1]. The technique is evaluated in a document recommendation application.
Expressive indexing languages are called for to obtain faithful representations of multimedia doc... more Expressive indexing languages are called for to obtain faithful representations of multimedia documents. They become a decisive factor to alleviate the noise problem, which is now often encountered with commercial search engines. In this case, noise consists in a great number of non-relevant answers to user's queries, which compromises interrogation efficiency. The use of complex formalisms to handle the problem is not straight-forward, as one of their general characteristics is to have high, sometimes unacceptable computational costs.
Abstract Conceptual graphs can be used as a simple and expressive language for indexing and retri... more Abstract Conceptual graphs can be used as a simple and expressive language for indexing and retrieving non-textual documents. In this knowledge representation formalism, the implementation of the matching function between a query and a document is obtained by the so-called projection operator between two conceptual graphs. A good implementation of the projection algorithm is therefore crucial for managing large bases of text and image documents. We present a new promising implementation.
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Papers by Iadh Ounis