Analyzing Two Approaches in Interdisciplinary Research: Individual and Collaborative

We propose a method for measuring interdisciplinary research by dividing it into two approaches: interdisciplinary research conducted by individual researchers and interdisciplinary research involving the collaboration of multiple researchers. Using this method, a database of “KAKENHI,” which is a grant-in-aid for scientific research provided by the Japan Society for the Promotion of Science (JSPS), is employed to measure interdisciplinary research from the perspective of the two research approaches, and the features of interdisciplinary research in KAKENHI are analyzed. The analysis results indicate the following: (1) the number of collaborative interdisciplinary research projects is larger than the number of individual interdisciplinary research projects, (2) the number of interdisciplinary research projects for each field and for each combination of fields differs among fields, and (3) the relationship between the numbers of interdisciplinary research projects in the two fields is asymmetric with regard to the main- and sub-fields of interdisciplinary research. As the proposed measurement method is capable of quantitatively measuring interdisciplinarity between fields and their research organizations, it will be useful for decision-makers in science and technology policy and strategy.