Visualization of Sets at the Web-of-Science using Bibliographic Coupling among Authors

[Loet Leydesdorff]

BibCoupl.exe for  <http://www.leydesdorff.net/software/isi/index.htm>
Bibliographic Coupling among Authors



BibCoupl.exe is freely available for academic usage. The program uses a set
saved using ISI's Web of Science as input, and generates various forms of
output:



1. cosine.dat provides an input file for Pajek as a visual representation of
the bibliographic coupling among authors within this set. The matrix is
normalized using the cosine.

2. coocc.dat and matrix.dbf are the files which underly cosine.dat.
Coocc.dat is the file before normalization; and matrix.dbf the asymmetrical
data matrix. The latter file can be used for statistical analysis in SPSS,
the former for graph-analytical analysis using UCINet.

3. Like ISI.EXE, the program BibCoupl.EXE produces four databases containing
the information in the original input set in relational format: au.dbf with
the authors; cs.dbf with the address ("corporate sources"); core.dbf with
information which is unique for each record (e.g., the title); and cr.dbf
containing the cited references. The files are linked through the numbers in
core.dbf. If one needs only these files, one is advised to use ISI.EXE,
since the computation of the cosine is computer intensive, and therefore
time-consuming.



The routine creating the matrix and the cosine-normalized output uses the
author names in the file au.dbf as variable names, and the records in cr.dbf
as the cases (rows). Initials in au.dbf are not considered because these may
vary among publications. The number of authors is limited to 1024, but the
number of cited references is unlimited.



The program is based on DOS-legacy software. It runs in a MS-Dos Command Box
under Windows. The programs and the input files have to be contained in the
same folder. The output files are written into this directory. Please, note
that existing files from a previous run are overwritten by the program. The
user is advised to save output elsewhere if one wishes to continue with
these materials.



input files



The input file has to be saved as a so-called marked list in the tagged
format from the Science Citation Index (Social Science Citation Index, Arts
& Humanities Citation Index) at the Web-of-Science. The default filename
"savedrecs.txt" should not be used, but "data.txt" instead.



output files



The program produces four output files in dBase IV format. These files can
be read into Excel and/or SPSS for further processing. They can also be used
in MS Access for relational database management. These files can be produced
by using the simpler ISI.EXE (which is much less intensive in the
computation).

Click here to download  <http://www.leydesdorff.net/software/isi.exe>
ISI.EXE



BibCoupl additionally produced two files with the extension ".dat"
(cosine.dat and coocc.dat) are in DL-format (ASCII) which can be read
directly into Pajek for the visualization (Pajek is freely available at
http://vlado.fmf.uni-lj.si/pub/networks/pajek/ ). A number of additional
databases are coproduced:



a. matrix.dbf contains the matrix of the cited references as the cases and
the authors in the set as the variables. The names of the authors before the
comma are used as the variables. The authors (column) are sorted
alphabetically and each row represents a cited reference in alphabetical
order. This file can be imported into SPSS for further analysis.



b. coocc.dbf contains a co-occurrence matrix of the authors from this same
data. This matrix is symmetrical and it contains the authors both as
variables and as labels in the first field. The main diagonal is set to
zero. The number of co-occurrences is equal to the multiplication of
occurrences in each of the texts. (The procedure is similar to using the
file matrix.dbf as input to the routine "affiliations" in UCINet, but the
main diagonal is here set to zero in this matrix.) The file coocc.dat
contains this information in the DL-format.



c. cosine.dbf contains a normalized co-occurrence matrix of the authors from
the same data. Normalization is based on the cosine between the variables
conceptualized as vectors (Salton & McGill, 1983). (The procedure is similar
to using the file matrix.dbf as input to the corresponding routing in SPSS.)
The file cosine.dat contains this information in the DL-format.

Click here to  <http://www.leydesdorff.net/Software/ISI/BibCoupl.EXE>
download BibCoupl.EXE



  _____

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.universal-publishers.com/book.php?method=ISBN&book=1581126956>
The Self-Organization of the Knowledge-Based Society;
<http://www.universal-publishers.com/book.php?method=ISBN&book=1581126816>
The Challenge of Scientometrics



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