The publication-citation matrix and its derived quantities

Abstract

We give an overview of the main data of a publication-citation matrix. We show how impact factors are defined, and, in particular, point out the difference between the synchronous and the diachronous impact factor. The advantages and disadvantages of using both as tools in research evaluation are discussed.

Measuring scientific performance of ISI indexed journals in economics: the impact of synchronous and diachronous impact factors

“…The reliability of the latter can be seen by tracking the upward and downward movement of journal rankings using Garfield (1955). As can be seen the existing impact factor distorts the scientific fairness (Ingwersen et al 2001) among the older and newer journals. Older journals may have accumulated higher citations on their scientific contents because of the higher degree of recognition based on concepts or issues.…”

“…In this study, Ingwersen et al (2001) diachronous approach was adapted to measure the impact factor based on non-self citations (NSC): Table 1 List of ISI indexed journals based on the two main groups (first and late comers) where DIFNSC is the DIF based on non-self-citations, NSC(Y ? i, Y) the non selfcitations for publications in the present and subsequent years, TP(Y) the total publications in the year Y, t the life expectancy of publications within a particular journal, m the ISI indexed journals in the subject category of Economics.…”

“…Whereas the synchronous impact factor is a backward approach, the diachronous impact factor is a forward approach. The former uses citations of publications of journals in a specified lagged year (Ingwersen et al 2001;Ingwersen 2012). It is also known as a retrospective approach (Glänzel et al 2004;Bouabid and Larivière 2013).…”

The Journal’s Integrated Impact Index: a new indicator for journal evaluation

“…The term 'diachronous' refers to the fact that the data used in the calculation are from different years with a starting point. Ingwersen and Larsen believe that diachronous impact factors for evaluation are more fair than synchronous impact factors, and they have given the reasons in their study (Ingwersen et al 2001). Meanwhile, this was also discussed by Iribarren-Maestro and Larsen (Iribarren-Maestro et al 2009).…”

Do open‐access journals in library and information science have any scholarly impact? A bibliometric study of selected open‐access journals using Google Scholar

“…The diachronous IF, thus, can be said to reflect development over time (Frandsen & Rousseau, 2005). Ingwersen, Larsen, Rousseau, and Russell (2001) discussed the detailed difference between synchronous and diachronous IFs and their use in research evaluation. Using both these synchronous and diachronous approaches, the present article principally searches for the answer to our research question: Do the openaccess (OA) journals in library and information science (LIS) have any scholarly impact?…”