Free text vs controlled vocabulary―retrieval precision and recall over large databases

The paper will examine the practical experience gained at the Leatherhead Food Research Association in the construction of a large scientifical/technical online database using both full text and controlled indexing techniques and comprises over 1 gigabyte of data. The implications to the user in terms of accuracy of recall were studied. The pitfalls and relative costs of both techniques will be described and the element of pragmatism that is needed for such databases will also be stressed