This paper suggests the use of proximity measurement in combination with the Okapi probabilistic model. First, using the Okapi system, our investigation was carried out in a distributed retrieval framework to calculate the same relevance score as that achieved by a single centralized index. Second, by applying a term-proximity scoring heuristic to the top documents returned by a keyword-based s...

This document describes the BM25 and BM25F implementation using the Lucene Java Framework. The implementation described here can be downloaded from [Pérez-Iglesias 08a]. Both models have stood out at TREC by their performance and are considered as stateof-the-art in the IR community. BM25 is applied to retrieval on plain text documents, that is for documents that do not contain fields, while BM...

Giraffidae is the only family of ruminants that is represented by two extant species; Okapia johnstoni and Giraffa camelopardalis. Of these taxa, O. johnstoni represents a typical short-necked ungulate, and G. camelopardalis exemplifies the most extreme cervical elongation seen in any ruminant. We utilize these two species to provide a comprehensive anatomic description of the cervical vertebra...

In this paper we describe our participation in CLEF-IP 2009 (prior-art search task). This was the first year of the task and we focused on how to build effectively a prior art query from a patent. Basically, we implemented simple strategies to extract terms from some textual fields of the patent documents and gave preference to title terms. We ran experiments with standard BM25 configurations a...

We describe a new technique for building a relevance judgment list (qrels) for TREC test collections with no human intervention. For each TREC topic, a set of new queries is automatically generated from key phrases extracted from the top k documents retrieved from 12 different Terrier weighting models when the initial TREC topic is submitted. We assign a score to each key phrase based on its si...

In this document, we describe our algorithms for automatic query expansion. The proposed algorithms are implemented in Java where the Lucene library 1 is modified and used by the proposed algorithms for document retrieval. In order to support accurate document retrieval, we have implemented the okapi(BM25) formulation 2 for measuring the document-query similarity measure. Three query expansion ...

Language models for information retrieval have received much attention in recent years, with many claims being made about their performance. However, previous studies evaluating the language modelling approach for information retrieval used different query sets and heterogeneous collections, which make reported results difficult to compare. This research is a broad-based study that evaluates la...

Stress is known to alter a variety of biological processes, including behavior and reproduction. It is therefore important to understand the stress levels of animals in captivity, especially those for whom captive breeding is a priority, such as the okapi. Levels of stress hormones can be measured from samples collected noninvasively, such as urine or feces, which are preferable with nondomesti...