Similarity Measures, Author Cocitation Analysis, and Information Theory, JASIST (forthcoming)

[Loet Leydesdorff]

The preprint version is now available at
http://www.leydesdorff.net/jasist04



The use of Pearson's correlation coefficient in Author Cocitation
Analysis was compared with Salton's cosine measure in a number of recent
contributions. Unlike the Pearson correlation, the cosine is insensitive
to the number of zeros. However, one has the option of applying a
logarithmic transformation in correlation analysis. Information calculus
is based on both the logarithmic transformation and provides a
non-parametric statistics. Using this methodology one can cluster a
document set in a precise way and express the differences in terms of
bits of information. The algorithm is explained and used on the data set
which was made the subject of this discussion.



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Loet Leydesdorff
Amsterdam School of Communications Research (ASCoR)
Kloveniersburgwal 48, 1012 CX Amsterdam
Tel.: +31-20- 525 6598; fax: +31-20- 525 3681
 <mailto:loet at leydesdorff.net> loet at leydesdorff.net ;
<http://www.leydesdorff.net/> http://www.leydesdorff.net/


 <http://www.upublish.com/books/leydesdorff-sci.htm> The Challenge of
Scientometrics ;  <http://www.upublish.com/books/leydesdorff.htm> The
Self-Organization of the Knowledge-Based Society

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