Ivo Anastácio

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In this paper, we compare different methods for the automatic assignment of geographic scopes to Web pages, based on place-names mentioned in the text. The methods under study are the Yahoo! Placemaker Web service, the hierarchy-based method originally proposed for the Web-a-Where system, the spatial overlap-based method originally proposed in the GIPSY(More)
This paper presents an approach for categorizing documents according to their implicit locational relevance. We report a thorough evaluation of several classifiers designed for this task, built by using support vector machines with multiple alternatives for feature vectors. Experimental results show that using feature vectors that combine document terms and(More)
Geotargeting is a specialization of contextual advertising where the objective is to target ads to Website visitors concentrated in well-defined areas. Current approaches involve targeting ads based on the physical location of the visitors, estimated through their IP addresses. However, there are many situations where it would be more interesting to target(More)
Geo-temporal information is pervasive over textual documents, since most of them contain references to particular locations, calendar dates, clock times or duration periods. An important text analytics problem is therefore related to resolving the place names and the temporal expressions referenced in the texts, i.e. linking the character strings in the(More)
This paper addresses the challenging information extraction problem of linking named entities in text to entries in a knowledge base. Our approach uses supervised learning to (a) rank candidate knowledge base entries for each named entity, (b) classify the top-ranked entry as the correct disambigua-tion or not, and (c) group together the named entities(More)
À memória do meu pai i Acknowledgments The conclusion of this work represents the end of a cycle that was only made possible with the support of various people, to whom I express my gratitude. First of all, I would like to thank Prof. Mário Figueiredo and Prof. Pedro Aguiar for having accepted to supervise my work and for their cooperation. I also thank(More)
The complexity and number of interconnected elements comprising today's networks have stressed the need for autonomic computing techniques. This need is even bigger in Wireless Sensor Networks, because sensor nodes should work continuously without operator intervention, i.e. have self-organiztaion and self-configuration algorithms. The first action that a(More)
Most text documents can be said to be related to some form of geographic context, although traditional text mining methods simply model documents as bags of tokens, ignoring other aspects of the encoded information. Recently , geographic information retrieval has captured the attention of many different researchers from fields related to text mining and(More)