61 An exploration of the science base of recent technology B.G. VAN VIANEN, H.F. MOED and A.F.J. VAN RAAN Scrence Studres Unrt, LISBON Instrtute, Unruersrty of Lerden, Statronsplern 242, 2312 AR Lerden, The Netherlands Final verston received September 1988 Thrs paper presents the results of a ftrst approach to study the science base of recent technological developments. Using the references in U.S. patents given to scienttftc literature (by patent examiners), we explore the possibility of identrfying this science base. These “citation linkages” between science and technology are studied for two datasets: all 1985 U.S. patents (worldwide invented) in the fields of chemical technology and pharmaceuticals; and all Dutch (Netherlands)-invented U.S. patents for all fields of technology, for the penod 1982-1985. With thts latter dataset, we focus on differences in science-base characteristtcs between two major technological fields: chem- ical technology and electrical/ electronics technology. After the analysis of some baste characteristics of the cited scienttfic literature, first approaches to the development of several types of science-base indicators are presented. The problem of calculation of the acttvity index for small to medium-sized countries IS signalled and a remedy IS proposed and applied. Wtth help of age dtstributions of patent references to scientific literature and the number of these references per patent, interesting differences between countries have been found. Companson of the Netherlands and other countries reveals some first mdications of the position of the Nether- lands in recent chemical technology. We also investigated the distribution of references to journals for different product groups. References are widely spread among journals. No clear field- or product-specific clusters of journals have been identi- fied, although some journals show “core-l&e” properttes. Fur- thermore, the distribution of the number of references per patent is found to be highly skewed. We conclude that the analysis of examiner-given references has yielded interesting results, but that the analysis of inven- tor-given references is a necessary further step in the study of the sctence base of technological developments. zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA 1. Introduction To a large extent, recent developments in tech- nology are based on scientific research. Invest- Research Policy 19 (1990) 61-81 North-Holland ment in research and development and cooper- ation with universities and other basic research institutions become increasingly important factors in the ability of countries and, in particular, of industries to keep pace with rapid technological advances. In this study, we explore the possibilities of identifying characteristics of the “science base” of technological developments by analysing the refer- ences (citations) in U.S. patents to scientific litera- ture. Such patent data carry important informa- tion on the science and technology interface since patent references to scientific publications can be seen as linkages between science and technology. Earlier studies of these “citation linkages” be- tween scientific literature (basic as well as applied research) and patents showed that patents in the “high-tech” fields (highly scientific areas of tech- nology) contain as many inventor-given citations to scientific publications as do research papers [2]. In this paper we focus on three main lines: (1) (2) (3) The development of indicators for the science base of recent worldwide chemical technology, again as far as this technology is reflected by (worldwide-invented) U.S. patents for the year 1985; an approach to analyse the position of the Netherlands with respect to the indicators as given in (1) in comparison with a number of other highly industrialized countries; the development of indicators for the science base of recent Dutch technology, as far as this technology is reflected by Netherlands-in- vented U.S. patents for the years 198221985. This paper presents a first approach to the above purposes and it is primarily based on the elaboration of a project agreement with Computer Horizons (CHI Research). 0048-7333/ X1/ $3.50 0 1990, Elsevter Science Publishers B.V. (North-Holland)