Averages of impact factors : general contribution

  • Leo Egghe Hasselt University
  • Ronald Rousseau Antwerp University
Keywords: journal impact, meta-journal, arithmetic average, geometric average, harmonic average, regression line, slope, monotone scatter plots


It is shown that the ratio of the harmonic mean of citations over the harmonic mean of publications does not lead to an acceptable impact measure for a meta-journal. This result contrasts markedly with the corresponding cases in which the arithmetic or geometric average is used. The relation between different averages and the regression of impact over publications or the regression of the opposite of impact over the opposite of publication numbers is studied in some detail. This leads to the general observation that if the regression line of y over x has a positive slope then this is not necessarily true for the regression line of 1/y over 1/x.
Research Articles