The Distribution of World Science

This Note reports some findings resulting from an exploratory analysis of the corporate tapes of the Science Citation Index (SCI), The analysis focuses on the international production of scientific literature, with a view to making a broad survey of national research activities. A narrower survey of international publication and citation activity was reported earlier for a handful of scientifically important countries.1 We have compared the international coverage of the SCI with the coverage of other abstracting and indexing services - such as Physics Abstracts, Chemical Abstracts, and Mathematical Reviews - and found it to be reasonably free from bias. The most serious bias we have found has been underrepresentation of the USSR in mathematics and biomedicine, and some underrepresentation of Japan. The extraction of the international publication data involved extensive computer manipulations of the corporate tapes. A count was made of publications (i.e. articles, notes, and reviews) associated with different national research-producing institutions. For example, if an author gave a his corporate address the University of London, the publication he authored would be assigned to the United Kingdom. When co-authorships indicated international collaboration in research, publications would be fractionally assigned to the respective countries of their authors. The 2,300 journals covered by the SCI in 1973 were further divided into 92 scientific subfields. These subfields are defined by the journals relevant to the subfields. For example, the subfield called microbiology is composed of articles published in 21 journals which are devoted to reporting research findings in microbiology. These subfields are in large measure defined by the citation patterns of publications. Journals with publications which cite each other heavily are generally assigned to the same subfield. Publications in multidisciplinary journals, such as Science, are fractionally assigned to the relevant fields which the journal represents. In order to make the present analysis tractable, the multitude of subfields were aggregated into eight fields: clinical medicine, biomedical research, biology, chemistry, physics, engineering and technology, earth and space