Purpose – Aims to review Fairthorne's classic article “Empirical hyperbolic distributions (Bradford‐Zipf‐Mandelbrot) for bibliometric description and prediction” ( Journal of Documentation , Vol. 25, pp. 319‐343, 1969), as part of a series marking the Journal of Documentation 's 60th...

Purpose – The purpose of this paper is to clarify earlier work on journal diffusion metrics. Classical journal indicators such as the Garfield impact factor do not measure the breadth of influence across the literature of a particular journal title. As a new approach to measuring research...

Purpose – The yield period of a journal is defined as the time needed to accumulate the same number of citations as the number of references included during the period of study. Yield sequences are proposed as journal attractivity indicators describing dynamic characteristics of a journal....

Purpose – This paper aims to introduce a general framework for the analysis of knowledge integration and diffusion using bibliometric data. Design/methodology/approach – The authors propose that in order to characterise knowledge integration and diffusion of a given issue (the source, for...

A new definition of the nuclear zone of a Bradford or Leimkuhler curve is proposed. A p‐nucleus is defined within which the gradient of the curve is less than the proportion p of its maximum value. This definition is invariant of scale and so is widely applicable. Using Egghe's fitting method...

Ajiferuke showed that observed author distributions can best be described by a shifted inverse Gaussian‐Poisson distribution. Yet, in the framework of a model to explain observed fractional distributions of authors it is important to know whether a simple one‐parameter distribution such as a...

A research model is proposed to prove or disprove the dependence of a field list of internationally visible journals on the initial set. Applications of the experiment are outlined. A conjecture is formulated concerning the validity of isi's impact factors.

Generally speaking, the three‐year synchronous impact factor is larger than the two‐year one. This follows from theoretical models derived from observations based on ISIÒs database. In this article we present an exception to this general rule, based on data from the Chinese Science Citation...