Search (4 results, page 1 of 1)

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Source

Universal classification II: subject analysis and ordering systems. Proc. of the 4th Int. Study Conf. on Classification research, Augsburg, 28.6.-2.7.1982. Ed.: I. Dahlberg

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Abstract

The second Cranfield experiment (Cranfield II) in the mid-1960s challenged assumptions held by librarians for nearly a century, namely, that the objective of providing subject access was to bring together all materials an a given topic and that the achieving of this objective required vocabulary control in the form of an index language. The results of Cranfield II were replicated by other retrieval experiments quick to follow its lead and increasing support was given to the opinion that natural language information systems could perform at least as effectively, and certainly more economically, than those employing index languages. When the results of empirical research dramatically counter conventional wisdom, an obvious course is to question the validity of the research and, in the case of retrieval experiments, this eventually happened. Retrieval experiments were criticized for their artificiality, their unrepresentative sampies, and their problematic definitions-particularly the definition of relevance. In the minds of some, at least, the relative merits of natural languages vs. indexing languages continued to be an unresolved issue. As with many eitherlor options, a seemingly safe course to follow is to opt for "both," and indeed there seems to be an increasing amount of counsel advising a combination of natural language and index language search capabilities. One strong voice offering such counsel is that of Robert Fugmann, a chemist by training, a theoretician by predilection, and, currently, a practicing information scientist at Hoechst AG, Frankfurt/Main. This selection from his writings sheds light an the capabilities and limitations of both kinds of indexing. Its special significance lies in the fact that its arguments are based not an empirical but an rational grounds. Fugmann's major argument starts from the observation that in natural language there are essentially two different kinds of concepts: 1) individual concepts, repre sented by names of individual things (e.g., the name of the town Augsburg), and 2) general concepts represented by names of classes of things (e.g., pesticides). Individual concepts can be represented in language simply and succinctly, often by a single string of alphanumeric characters; general concepts, an the other hand, can be expressed in a multiplicity of ways. The word pesticides refers to the concept of pesticides, but also referring to this concept are numerous circumlocutions, such as "Substance X was effective against pests." Because natural language is capable of infinite variety, we cannot predict a priori the manifold ways a general concept, like pesticides, will be represented by any given author. It is this lack of predictability that limits natural language retrieval and causes poor precision and recall. Thus, the essential and defining characteristic of an index language ls that it is a tool for representational predictability.