Information retrieval (IR) has most usually been construed as the problem of selecting texts from a database in response to some more-or-less well-specified query. From this point of view, the major issues of concern to IR have been the representation of texts, and of queries, and techniques for the comparison of text and query representation. This 'standard' view of IR is perhaps most succinctly represented in the diagram of Figure 1.
From Figure 1, we see that the standard view of IR has comparison of text surrogate and query as its central process. This comparison in turn depends upon the two representation processes. In practice, most emphasis has been placed upon the process of text representation, with relatively little work having been done on the development of representation schemes specific to information needs or problems. Concern with representation of the information need has typically arisen after the process of judgment, which is typically to be performed by the user, as an estimate of the potential relevance of the text to the information need. The results of the judgement process are then used by the system to modify the query, or, occasionally to modify the text representations. This process of query modification, or 'relevance feedback', is perceived, in the standard view of IR, as an attempt to gain the 'best' possible representation of the user's query, or 'information need', in order to select the texts most likely to be relevant to that query ; that is, to improve the representation so that the comparison process will work most effectively. It is important to recognize that, in this model of IR, the person involved in IR is seen as a user of the system, standing outside of it. Involvement of the user with the IR system is minimal, and interaction (in the form of the judgment process) is seen as ancillary to, and only in support of, the representation and comparison processes.