Wrapper Generation with Patricia Trees
نویسندگان
چکیده
The automatic processing of search results that stem from Web-based search interfaces has come into focus, and it will remain important (as long as XML is not a universally applied technology). The reasons for this are twofold: (1) The need for value-added services such as filtering or graphical preparation of search results will increase. (2) The manual creation of tailored parsers for the information extraction from HTML pages cannot keep pace with the fast changing presentation of the search results in right these pages. Automatic wrapper generation addresses this problem. It means the construction of a tailored parser for a certain type of HTML page with a minimum of manual intervention. This paper introduces the state of the art and presents an own development: A two-stage approach that combines highly efficient suffix matching based on a modified Patricia tree along with a knowledge-based analysis of candidate token sequences.
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