The Design and Production of a Citation Index

There is little, if anything, that is simple at all levels of reality. Citation indexing is no exception. At the conceptual level, it provides a simple way around the semantic, intellectual, and economic problems of traditional subject-term indexing (see Chapter One: “A Conceptual View of Citation Indexing”). At the implementation level, however, citation indexing loses much of that simplicity, particularly when it is being implemented on a large scale. The basic implementation complexities lie in the areas of coverage and production, which are related in a direct way by economics: the more efficient the production process, the more literature one can afford to cover. Though the nature and magnitude of the complexities vary somewhat according to the scope of the index (see Chapter Two: “An Historical View of Citation Indexing”), the best illustration of them, and of their relationship, is the Science Citation Index. Because its scope is so much broader than any other citation index to scientific literature, it demonstrates better than any other what is involved in realizing the single most important attribute of the citation-indexing concept-the ability to provide an integrated view of the scientific literature that is unrestricted by disciplinary boundaries.