Dempster-Shafer’s Theory of Evidence applied to Documents: modelling Uncertainty

Documents ojlen display a structure determined by the author, e.g., several chapters, each with several sub-chapters and so on. Taking into account the structure of a document allows the retrieval process to focus on those parts of the documents that are most relevant to an information need. Chiaramella et al advanced a model for indexing and retrieving structured documents. Their aim was to express the model within a framework based on formal logics with associated theories. They developed the logical formalism of the model. This paper adds to this model a theory of uncertainty, the Dempster-Shafer theory of evidence. It is shown that the theory provides a rule, the Dempster’s combination rule, that a[lows the expression of the uncertainty with respect to parts of a document, and that is compatible with the iogica{ model developed by Chiaramella et al.