A Universal Model for XML Information Retrieval

Abstract

Abstract. This paper presents an approach for extending the vector space model (VSM) to perform XML retrieval. The model is extended to support important aspects of XML structural and semantic information such as element nesting level, matching tag names in the query and the collection and the relation between tag names and content of an element. Potential use of the model for heterogeneous as well as for the unstructured collection is also shown. We compared our model with the standard vector space model and obtained a gain for unstructured and structured queries. For unstructured collections the vector space model effectiveness is preserved.

Managing structured queries in probabilistic XML retrieval systems

“…XML is in fact a meta-language as its main objective is to facilitate the creation of markup languages to represent structured data 3 (this is one of the main differences with HTML, as XML is used to describe rather than show data, as HTML does).…”

“…An asterisk * selects all the elements placed in the path after it (/A//B// * ) (for example, /email//* would select all the descendants of email). Finally, a pair of opening and closing brackets and a number between them, after an element, establishes the order of the element as a child from left to right: //A/B [3] means that the XPath expression engine would select the third B element child of A.…”

“…In [3], the authors modify the VSM including new XML specific features: the nesting nature of the XML elements and the fact that each element could be retrieved. The authors design a new ranking function similar to the cosine measure for flat documents.…”

Processing Heterogeneous Collections in XML Information Retrieval

“…In our previous paper [3], we have defined how the standard vector space model [10] [11] was adapted to process an XML document whose relevance is given by:…”

“…Our model [3] is based on the observation and theorical confirmation [1] that the tags of an XML [4] document are semantically related to the content that they delimit. We consider the structure of the XML standard as a new source of evidence, able to assist in the identification of the information contained in the documents without being essential to its identification.…”