Demos: Concept Algebra Toolbox (CAT)

algebra1algebra2A set of Matab tools for complexity measurement and algebraic analysis of discrete-featured concepts

v1.0 by Jacob Feldman

Instructions for use:

1. Download the archive (zip file) and decompress it wherever you want it. It will create a directory called Algebra.
2. In Matlab, cd into the Algebra directory.
3. To use the graphical user interface (recommended): at the Matlab prompt, type ‘complexity_tool’. The GUI should appear.
4. For documentation and explanation of syntax, type ‘help algebra’ at the Matlab prompt. This gives a list of available command-line routines with brief explanations.

Click here to download the CAT (v1.0): zip

The concept algebra and its associated complexity measure (algebraic complexity) are described in Feldman (2006) "An algebra of human concept learning" (J. Mathematical Psychology, 50, 339-368). You can also find synopses and elaborations Feldman (2003) "How surprising is this simple pattern? Quantifying 'Eureka!'" (Cognition, 93, 199-224; see Appendix I) and Aitkin, C. D. and Feldman, J. (2006) "Subjective complexity of categories defined over three-valued features." (Proceedings of the Cognitive Science Society)

Please email the author (This email address is being protected from spambots. You need JavaScript enabled to view it.) with questions or comments.

Screenshot of complexity_tool in action, showing a 5-object concept defined over a 2x2x3-valued feature grid:


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