Extraction of Flat and Nested Data Records from Web Pages

This paper studies the problem of identification and extraction of flat and nested data records from a given web page. With the explosive growth of information sources available on the World Wide Web, it has become increasingly difficult to identify the relevant pieces of information, since web pages are often cluttered with irrelevant content like advertisements, navigation-panels, copyright notices etc., surrounding the main content of the web page. Hence, it is useful to mine such data regions and data records in order to extract information from such web pages to provide value-added services. Currently available automatic techniques to mine data regions and data records from web pages are still unsatisfactory because of their poor performance. In this paper a novel method to identify and extract the flat and nested data records from the web pages automatically is proposed. It comprises of two steps : (1) Identification and Extraction of the data regions based on visual clues information. (2) Identification and extraction of flat and nested data records from the data region of a web page automatically. For step1, a novel and more effective method is proposed, which finds the data regions formed by all types of tags using visual clues. For step2, a more effective and efficient method namely, Visual Clue based Extraction of web Data (VCED), is proposed, which extracts each record from the data region and identifies it whether it is a flat or nested data record based on visual clue information – the area covered by and the number of data items present in each record. Our experimental results show that the proposed technique is effective and better than existing techniques.