Compound words: A problem in post‐coordinate retrieval systems

Compound words cause some difficulty in post‐coordinate indexing systems: if too many are fractured, or the wrong categories are selected for fracturing, noise will be produced at unacceptable levels on retrieval. Various prior suggestions for handling compound terms are examined which include those for precoordinated or rotated, indexes. The syntactic origins are also explored and it is found that many compound words hinge on a prepositional relationship between the components, and that this relationship can be applied to decision making. Other compound words are in effect abbreviated statements from longer phrases, while some are influenced by the presence of a verb‐like form. These syntactic influences, together with some of the philosophy from earlier studies–especially that of the ‘force’ required to fracture a term, have been combined to produce a set of rules which have been employed at the Natural Rubber Producers' Research Association (NRPRA) for over two years. These have greatly eased decision making and have enabled the thesaural vocabulary to be made more consistent. It is also suggested that the rules have some bearing on the application of roles especially if these are employed on a pre‐coordinate basis.