Affiliations: [a] Faculty of Electrical and Computer Engineering, Malek-Ashtar University of Technology, Iran | [b] Department of Computer Engineering, Iran University of Science and Technology, Iran
Correspondence:
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Corresponding author: Mahdi Naghibi, Faculty of Electrical and Computer Engineering, Malek-Ashtar University of Technology, Iran. Tel.: +98 21 22945141; Fax: +98 21 22935341; E-mail: mahdi110@gmail.com.
Abstract: Access to one of the richest data sources in the world, the web, is not possible without cost. Often, this cost is not taken into account in data acquisition processes. In this paper, we introduce the Learning Agents (LA) method for automatic topical data acquisition from the web with minimum bandwidth usage and the lowest cost. The proposed LA method uses online learning topical crawlers. The online learning capability makes the LA able to dynamically adapt to the properties of web pages during the crawling process of the target topic, and learn an effective combination of a set of link scoring criteria for that topic. That way, the LA resolves the challenge in the mechanism of combining the outputs of different criteria for computing the value of following a link, in the formerly approaches, and increases the efficiency of the crawlers. A version of the LA method is implemented that uses a collection of topical content analyzers for scoring the links. The learning ability in the implemented LA resolves the challenge of the unclear appropriate size of link contexts for pages of different topics. Using standard metrics in empirical evaluation indicates that when non-learning methods show inefficiency, the learning capability of LA significantly increases the efficiency of topical crawling, and achieves the state of the art results.
Keywords: Cost-sensitive learning, data acquisition, learning agent, topical crawler, web data mining
