From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/4436 Path: news.gmane.org!not-for-mail From: mjhealy@ece.unm.edu Newsgroups: gmane.science.mathematics.categories Subject: New technical report available Date: Tue, 1 Jul 2008 18:16:14 -0600 (MDT) Message-ID: NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain;charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable X-Trace: ger.gmane.org 1241019945 13298 80.91.229.2 (29 Apr 2009 15:45:45 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 29 Apr 2009 15:45:45 +0000 (UTC) To: categories@mta.ca Original-X-From: rrosebru@mta.ca Wed Jul 2 09:27:22 2008 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Wed, 02 Jul 2008 09:27:22 -0300 Original-Received: from Majordom by mailserv.mta.ca with local (Exim 4.61) (envelope-from ) id 1KE1Jn-0003NW-9b for categories-list@mta.ca; Wed, 02 Jul 2008 09:20:15 -0300 Original-Sender: cat-dist@mta.ca Precedence: bulk X-Keywords: X-UID: 3 Original-Lines: 48 Xref: news.gmane.org gmane.science.mathematics.categories:4436 Archived-At: A new University of New Mexico technical report is available on DSpace, ECE-TR-08-0010. It describes an experiment in cognitive psychology that tests a (mathematical) category-theoretic model of categorization by humans. The model is part of a comprehensive theoretical model of the declarative semantics of neural networks. The report can be obtained by going to DSpaceUNM, or directly to http://hdl.handle.net/1928/6724 . Questions and comments are welcome. Mike Healy Electrical and Computer Engineering University of New Mexico Albuquerque, NM USA Abstract Categorization and the judgement of similarity are fundamental in cognition. We propose that these and other activities are based upon an underlying structure of knowledge, or concept representation, in the brain. Further, we propose that this structure can be represented mathematically in a declarative form via category theory, the mathematica= l theory of structure. We test the resulting mathematical model in an experiment in which human subjects provide judgements of similarity for pairs of line drawings using a numerical scale to represent degrees of similarity. The resulting numerical similarities are compared with those derived from the category-theoretic model by comparing diagrams. The diagrams represent distributed concept structures underlying the line drawings. To compare with a more conventional analysis technique, we also compare the human judgements with those provided by a two-dimensional feature space model equipped with a distance metric for the line drawings= . The results are equally favorable for both models. Because of this and the putative explanatory power of the category-theoretic model, we propos= e that this model is worthy of further exploration as a mathematical model for cognitive science. Keywords categorization, (mathematical) category, cognition, colimit, concept, diagram, feature, morphism, similarity, theory