TRENDS IN ... A CRITICAL-REVIEW - ON THE ROLE OF LOGIC IN INFORMATION-RETRIEVAL

The logical approach to information retrieval has recently been the ob ject of active research. It is our contention that researchers have pu t a lot of effort in trying to address some difficult problems of IR w ithin this framework, but little effort in checking that the resulting models satisfy those well-formedness criteria that, in the field of m athematical logic, are considered essential and conducive to effective modelling of a real-world phenomenon. The main motivation of this pap er is not to propose a new logical model of IR, but to discuss some ce ntral issues in the application of logic to IR. The first issue we tou ch upon is the logical relationship we might want to enforce between f ormulae d, representing a document, and n, representing an information need; we analyse the different implications of models based on truth, validity or logical consequentiality. The relationship between this i ssue and the issue of partiality vs. totality of information is subseq uently analysed, in the context of a broader discussion of the role of denotational semantics in IR modelling. Finally, the relationship bet ween the paradoxes of material implication and the (in)adequacy of cla ssical logic for IR modelling purposes is discussed. (C) 1998 Elsevier , Science Ltd. All rights reserved.