This paper describes and evaluates various stemming and indexing strategies for the Russian language. We design and evaluate two stemming approaches, a light and a more aggressive one, and compare these stemmers to the Snowball stemmer, to no stemming, and also to a language-independent approach (n-gram). To evaluate the suggested stemming strategies we apply various probabilistic information r...

We use the Okapi retrieval system to conduct the email discussion search. The following issues are investigated. First, we make use of the thread structure in the emails to re-rank the documents retrieved by Okapi. We would like to see whether such post-processing of the retrieval result can boost the retrieval performance. Second, in terms of query formulation, we investigate whether the use o...

In TREC-10, Microsoft Research China (MSRCN) participated in the Web track (ad hoc retrieval task and homepage finding task). The latest version of the Okapi system (Windows 2000 version) was used. We focused on the developing of content-based retrieval and linkbased retrieval, and investigated the suitable combination of the two. For content-based retrieval, we examined the problems of weighti...

This paper describes our participation in the TREC 2006 Genomics evaluation campaign. In an effort to find text passages that will meet user requests, we propose and evaluate a new approach to the generation of orthographic variants of search terms (mainly genomic names in our case). We also evaluate the retrieval effectiveness of both the Okapi (BM25) model and the I(n)B2 probabilistic model d...

The present work describes the effects of winter and spring genotypes of rapeseed (PF7045/91, Okapi and Opera), explants (cotyledons and hypocotyls), light, different kinds and concentrations of auxins [Naphthylacetic acid (NAA) and 2, 4dichlorophenoxyacetic acid (2, 4-D)], presence of cytokinin [benzyladenine (BA)] and different concentrations of micro and macro elements (MS and 1/2MS) on call...

Our approach to the ImageCLEF 2010 tasks is based on Histogram of Oriented Gradients descriptors (HOG) and Okapi BM25 based text retrieval. We extracted feature vectors to describe the visual content of an image region or the entire image. We trained a Gaussian Mixture Model (GMM) to cluster the feature vectors extracted from the image regions. To represent each image with only one vector we co...

Mercure is an information retrieval system based on a connexionist approach and modeled by a multi-layer network. The network is composed of a query layer (set of query terms), of a term layer (representing the indexing terms) and of a document layer [Bougha 99]. Mercure includes the implementation of retrieval process based on spreading activation forward and backward through the weighted link...

THISL is an ESPRIT Long Term Research Project focused the development and construction of a system to items from an archive of television and radio news broadcasts. In this paper we outline our spoken document retrieval system based on the ABBOT speech recognizer and a text retrieval system based on Okapi term-weighting . The system has been evaluated as part of the TREC-6 and TREC-7 spoken doc...