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Abstract

Describes a method for analysing the diffusion of scientific journals, using the Rasch model as the measuring instrument. It is applied to the 10-year distribution of citations to journals of the subject category 'physics' by year of publication of cited articles with data obtained from the SCI Journal Citation Reports of ISI for the year 1994. Diffusion in a scientific field would be regarded as the dissemination of knowledge, channelled through citations that an distributed over different periods of time and propagated by means of scientific journals: here it is considered to be a latent variable defined by a particular set of items (the citations made in different time periods), and the Rasch model is used as an instrument for measuring that variable

Source

Journal of the American Society for Information Science. 48(1997) no.10, S.953-958

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Abstract

We present a bibliometric study of a corpus of 839 bibliographic references about automatic indexing, covering the period 1956-2000. We analyse the distribution of authors and works, the obsolescence and its dispersion, and the distribution of the literature by topic, year, and source type. We conclude that: (i) there has been a constant interest on the part of researchers; (ii) the most studied topics were the techniques and methods employed and the general aspects of automatic indexing; (iii) the productivity of the authors does fit a Lotka distribution (Dmax=0.02 and critical value=0.054); (iv) the annual aging factor is 95%; and (v) the dispersion of the literature is low.

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Abstract

The growth of scientific output in recent years has meant that fewer libraries are able to offer the entire range of journals, with the others being forced to make a selection. The objective of the present work is to describe criteria to regulate the selection of theses journals to provide the researcher with the information that is most being used in research. One form of quantifying this information is by way of the citations that papers receive over a period of time following their publication. Obsolescence, expressed in terms of an annual aging factor, does not reflect the real behaviour of most papers. An alternative is the use of 'topicality', considered as a latent variable, with the Rasch model as the measuring instrument. We considered 45 physics journals, and found the results of applying the Rasch model to be more satisfactory than those obtained with the annual aging factor

Source

Journal of the American Society for Information Science. 51(2000) no.9, S.812-815

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Abstract

Focuses on a way to determine a ranking of science journals according to the number of citations-to and items-published data used by Science Citation Insitute of Citation Reports of the Institute for Science Information to determine journal ranking by impact factor. Applies latent traits theory to bibliometrics

Source

Journal of the American Society for Information Science. 47(1996) no.6, S.458-467