Hypermedia – Information Retrieval and Browsing
4 Information Retrieval and Browsing
Lucarella has written that whereas conventional IR techniques focus on “what to where” (we know what we want, but we wish to find out where in the database it is), hypertext browsers focus on “where to what” (we know where we are, but we want to know what is there) [Lucarella, 1990]. IR in a hypertext system can combine these two techniques to greatly enhance the process of finding relevant information. Hypertext browsing can supplement conventional IR by allowing users to discover retrieval cues that successively can be used for query formulation. Query facilities can supplement hypertext browsing by providing the user with a set of relevant nodes for browsing.
In a query language developed for HDM2, a query produces a list of references to items which can be units, composites, indexes, or guided tours. These can be used as a dynamic access structure (or virtual structure) from which further navigation can originate. The navigation space resulting from such a query or filter is called a hyperview. All subsequent requests (either queries or navigation commands) will be interpreted only within this restricted space [Garzotto et al., 1993].