Page 130 - DLIS402_INFORMATION_ANALYSIS_AND_REPACKAGING

Unit 6: Information Retrieval Model and Search Strategies

systems than those which have been characteristically assumed in information retrieval research. Notes
Two paradigms have been distinguished in information retrieval research, the cognitive and the
physical, but they share the assumption of the value of delivering relevant records. For the purposes
of the discussion here, they can be considered as a single, if heterogeneous, paradigm, linked if not
united, by this common assumption.
The contrasting paradigm implicitly embodied in classification and indexing may finally be
incommensurable with that of information retrieval research, with disputes not logically resolvable
within either paradigm. The approach taken in this paper will be suggested:
That an alternative principle involving discriminatory power has been held, implicitly and explicitly,
in a number of largely separate discourses;
That the cumulative effect of recognising this is to indicate more viable and productive criteria for
designing, using and evaluating information retrieval systems; and, finally, that the classical tradition
of information retrieval research can itself be assimilated to the new model.
In this final respect, the development proposed here is an exemplar of scientific development in
which discarded paradigms are absorbed into developing ones, as special cases.
The discourses in which an alternative principle for the design and evaluation of information retrieval
systems can be discovered and which are to be covered here are:
An emerging, although rather isolated and discontinuous, strand of information retrieval research;
Accepted discussions of the principles of classification and indexing;
Giambattista Vico’s critique of Aristotelian principles and categories for classification;
and, most crucially, ordinary language discussion of information systems.

Information Retrieval Research

Information retrieval research, particularly in the experimental tradition emerging in the 1950s in
Britain and North America, has taken as its founding assumption the principle that an ideal information
system should deliver all (and possibly only all) the records relevant to a given information need. In
order to evaluate information systems in relation to this desired end, or variations on it, various steps
were taken: relevance was stabilised and quantified, sometimes being reduced to a binary or
dichotomous variable; and measures of precision and recall, which depend on the prior stabilisation
of relevance, were developed.
More recent research has questioned the validity of aspects of this paradigm, although more
frequently with reference to its subsidiary concepts (relevance and information need) and derived
measures (precision and recall) than with regard to its founding assumption.
The adequacy of the concept of relevance employed information retrieval research has been
questioned. Experiments substitute a measurable phenomenon, relevance as constructed under
artificial conditions, for an immeasurable one, relevance under operational conditions, but fail to
demonstrate that there is an adequate correlation between the two. Most disturbingly, it has been
suggested that operational relevance is fluid, influenced by intention, context, and other documents
seen or read, and simply not amenable to stabilisation or, further, quantification.
The classical measures of precision and recall are also rendered increasingly artificial by the high
degree of interactivity enabled by recent information technology developments. How, when
searching a CD-ROM database, is the final set of records to be isolated except by a process whose
very arbitrariness invalidates it as a component of a measure of system performance? High
interactivity, and unmediated searching, also reduces the need for a query to be fully articulated in
advance of searching.

LOVELY PROFESSIONAL UNIVERSITY 125