Hermann Helbig, Carsten Gnorlich, and Dirk Menke
The paper describes two methods for realizing a user-friendly access to distributed information resources. The first method (Method I) based on a ibrm-driven dialogue, which is used in the project named "MEDOC". It aims at experienced user who is familiar with attribute value structures of the data base schemes typical information retrieval systems (IRS) and who knows the definition of boolean operators. The second method (Method II) applied in the system LINAS is from the very beginning oriented towards natural language communication between end-users and IRSs. Both methods can be used in an interface between the user and an information brokering system helping him/her to find an appropriate information provider for his/her demands in networked information systems. Method I gives the user certain guidance in formulating his/her queries but has a restricted expressive power. It almost never supports the user in automatically finding more complicated descriptional elements, as for instance classificators of a standardized classificational system. Method II, on the other hand, is devoted to the "naive user" having no experience with information retrieval techniques. Allowing for an unrestricted natural language input, it is distinguished by a greater expressive power and gives valuable support in automatically finding descriptors and classificational categories used in the description of documents. In comparison with Method I, there is less guidance in formulating the user’s demands.