A theory of continuous rates and applications to the theory of growth and obsolescence rates

https://doi.org/10.1016/0306-4573(94)90070-1Get rights and content

Abstract

For functions ƒ of a continuous variable t, we define the term “rate” (as, e.g., rate of growth or of obsolescence) as the exponential function of the derivative of the logarithm of this function (i.e., e(logƒ)'). This replaces discrete calculations, such as ƒ(t + 1)ƒ(t), which is not so appropriate in this continuous context. We investigate this transformation (which is in fact the exponential function of the Fechner law), and show that it indeed has all properties that we can expect from a “rate” function. We then apply these findings to the results of three previous papers and again prove the main results in this continuous setting.

References (18)

  • L. Egghe et al.

    Citation age data and the obsolescence function: Fits and explanations

    Information Processing & Management

    (1992)
  • G. Archibald et al.

    The size and growth of serial literature 1950–1987, in terms of the number of articles per serial

    Scientometrics

    (1990)
  • B.C. Brookes

    Obsolescence of special library periodicals: Sampling errors and utility contours

    Journal of the American Society for Information Science

    (1970)
  • B.C. Brookes

    The growth, utility and obsolescence of scientific periodical literature

    Journal of Documentation

    (1970)
  • Q.L. Burrell

    A note on ageing in a library circulation model

    Journal of Documentation

    (1985)
  • Q.L. Burrell

    A second note on ageing in a library circulation model: The correlation structure

    Journal of Documentation

    (1986)
  • Q.L. Burrell

    A third note on ageing in a library circulation model: Application to future use and relegation

    Journal of Documentation

    (1987)
  • Q.L. Burrell

    On the growth of bibliographies with time: An exercise in bibliometric prediction

    Journal of Documentation

    (1989)
  • B. Carter et al.

    Changes in the use of sociological articles with time: A comparison of diachronous and synchronous data

    British Library Lending Review

    (1974)
There are more references available in the full text version of this article.

Cited by (18)

  • Quantifying the online long-term interest in research

    2022, Journal of Informetrics
    Citation Excerpt :

    Generally, obsolescence studies are synchronous because these are easier than diachronous studies to conduct. For functions of a continuous variable, Egghe (1994) defined the term rate of growth or obsolescence as an exponential function of the derivative of the log of the function. Egghe (1993); Egghe et al. (1995) observed that the rate of obsolescence varies and that this variation can be calculated as a utilization (mathematical) function.

  • Growth of Literature on Bradford's Law

    2016, Investigacion Bibliotecologica
    Citation Excerpt :

    Five years later, Stevens (1953) publishes and paper citing Vickery (1948) and Bradford (1948) in which he explains the features of dispersion of specialized literature. In the early 1960s, three references to Bradford appear, i.e., Fourmont and Kervégant (1960), Kendall (1960) and Cole (1962). Every year from 1966 and until 2012 an average of 12 papers per year employing the strategies proposed by Bradford (1934, 1948) were found in the sample under study.

  • Growth of Literature on Bradford's Law

    2016, Investigacion Bibliotecologica
View all citing articles on Scopus
View full text