Patent Classification as Indicators of Cognitive Structures

Pikas, Christina K. Christina.Pikas at JHUAPL.EDU
Fri Mar 23 11:25:39 EDT 2007

It suggests to me that it might be a faceted classification system - or
a system that is applied in a faceted manner.
For the purposes of a sort of thought experiment, we might consider MeSH
to be faceted.  For an article on say leg fractures of adult human males
we might have fractures, bone
femur OR Fibula OR Patella OR Tibia
femoral neck fractures, etc.
maybe even "activity"/adverse effects or some such...
If you tried to cluster on, say, femur you would get a weak
co-classification because there are indeed many articles on leg breaks,
but also bone cancer and genetic anomalies, etc.
Maybe I should read the article :)

Christina K. Pikas, MLS 
R.E. Gibson Library & Information Center
The Johns Hopkins University Applied Physics Laboratory 
Voice  240.228.4812 (Washington), 443.778.4812 (Baltimore) 
Fax 443.778.5353 


From: ASIS&T Special Interest Group on Metrics
[mailto:SIGMETRICS at LISTSERV.UTK.EDU] On Behalf Of David E. Wojick
Sent: Friday, March 23, 2007 11:38 AM
Subject: Re: [SIGMETRICS] Patent Classification as Indicators of
Cognitive Structures

I have a general theory of the structure of information that may be
relevant. I have not published it but there is a brief essay on it here:

It suggests that in typical cases there will be many useful ways to
systematically organize or classify a given body of information. If so
then there is probably no single way that will be generally useful or
representative. A working instance of this principle is the NASA
taxonomy system, with 11 independent taxonomies. However, many of the
underlying structures are not taxonomies, nor even tree-structures. Many
are networks with convergence as well as tree-like divergence.

Interestingly, since some of these structures are based on the way the
things the information is about are related to one another, some of the
most important structures are unknown until science finds them.

David Wojick

 info for SIGMETRICS (for example unsubscribe):

Patent Classifications as Indicators of Cognitive Structures

Paper to be presented at the Annual Meeting of the

Society for the Social Studies of Science (4S),

Montreal, October 2007

*       pdf-version of the full paper

*       html-version of the full paper

Using the 138,751 patents filed in 2006 under the Patent Cooperation
Treaty, co-classification analysis is pursued on the basis of three- and
four-digit codes in the International Patent Classification (IPC, 8th
edition). The initial hypothesis that classifications might be
considered as the organizers of patents into classes, and that therefore
co-classification patterns would be useful for mapping, is discarded in
favor of using co-word analysis among titles of patents. The
classifications hang weakly together, even at the four-digit level; at
the country level, more specificity can be made visible. The
co-classifications among the patents enable us to analyze and visualize
the relations among technologies at different levels of aggregation.
However, countries are not the appropriate units of analysis because
patent portfolios are largely similar in many advanced countries in
terms of the classes attributed.

The following files are input files for Pajek based on the cosines
between the 4-digit classifications for each country separately and for
the complete set ("World"):

World <>  (135,536 patents;


Andorra <>  (4 patents)
United Arab Emirates <>  (15
Antigua and Barbuda <>  (4
...., etc.

Spain <>  (1114 patents)
Finland <>  (1651 patents)
France <>  (6958 patents;
...., etc.

Netherlands <>  (3287 patents)
Norway <>  (665 patents)
New Zealand <>  (444 patents)

....., etc.

Loet Leydesdorff
Amsterdam School of Communications Research (ASCoR)
Kloveniersburgwal 48, 1012 CX Amsterdam
Tel.: +31-20- 525 6598; fax: +31-20- 525 3681
loet at ;

Now available: The Knowledge-Based Economy: Modeled, Measured, Simulated
8> . 385 pp.; US$ 18.95 
The Self-Organization of the Knowledge-Based Society
6> ; The Challenge of Scientometrics



"David E. Wojick, Ph.D." <WojickD at>
Senior Consultant -- The DOE Science Accelerator
A strategic initiative of the Office of Scientific and Technical
Information, US Department of Energy

(540) 858-3150 
391 Flickertail Lane, Star Tannery, VA 22654 USA provides my bio and
client list.
presents some of my own research on information structure and dynamics. 

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