R-cluster indicators for measuring the evolutionary rhythm of science based on a general p-c matrixR-cluster indicators for measuring the evolutionary rhythm of science based on a general p-c matrix
Faculty of Social Sciences. Instructional and Educational Sciences
Information, Emancipation and Development
Documentation and information
Journal of the China Society for Scientific and Technical Information
26(2007):6, p. 877-885
University of Antwerp
A general P-C matrix of a set of articles is composed of two parts:publication data and citation data.Based on a general P-C matrix and introducing the notion of"isochronicity",a key measure,denoted as C_k,is created.Here the symbol C_k.represents the average number of citations of the articles,published in different years,in the k~(th) year after their publications. The creation of C_k leads to the construction of R-cluster indicators for measuring the evolutionary rhythm of science.The rhythm indicator is the ratio of observation-based citation data and expectation-based citation data.The R-cluster consists of four indicators [deleted]①R indicator,with visual angle of cited year and triangle citation window;②R' indicator,with visual angle of cited year and parallelogram citation window;③r indicator,with visual angle of citing year and triangle citation window;④r' indicator,with visual angle of citing year and parallelogram citation window.Taking the Journal of Documentation as an example this article illustrates how to calculate the R sequences and how to apply the R-cluster indicators.