ON THE CREATION OF HYPERTEXT LINKS IN FULL-TEXT DOCUMENTS - MEASUREMENT OF INTER-LINKER CONSISTENCY

An important stage in the process of retrieval of objects from a hypertext database is the creation of a set of inter-nodal links that are intended to represent the relationships existing between objects; this operation is often undertaken manually, just as index terms are often manually assigned to documents in a conventional retrieval system. Studies of conventional systems have suggested that a degree of consistency in the terms assigned to documents by indexers is positively associated with retrieval effectiveness. It is thus of interest to investigate the consistency of assignment of links in separate hypertext versions of the same full-text document, since a measure of agreement may be related to the subsequent utility of the resulting hypertext databases. The calculation of values indicating the degree of similarity between objects is a technique that has been widely used in the fields of textual and chemical information retrieval; in this paper, we describe the application of arithmetic coefficients and topological indices to the measurement of the degree of similarity between the sets of inter-nodal links in hypertext databases. We publish the results of a study in which several different sets of links are inserted, by different people, between the paragraphs of each of a number of full-text documents. Our results show little similarity between the sets of has identified by different people; this finding is comparable with those of studies of inter-indexer consistency, where it has been found that there is generally only a low level of agreement between the sets of index terms assigned to a document by different indexers.