# Info on Balance Scale Weight & Distance Data Base

    1. Title: Balance Scale Weight & Distance Database

    2. Source Information:
        (a) Source: Generated to model psychological experiments reported
    		by Siegler, R. S. (1976).  Three Aspects of Cognitive
    		Development.  Cognitive Psychology, 8, 481-520.
        (b) Donor: Tim Hume (hume@ics.uci.edu)
        (c) Date: 22 April 1994

    3. Past Usage: (possibly different formats of this data)
       - Publications
    	1. Klahr, D., & Siegler, R.S. (1978).  The Representation of
    	   Children's Knowledge.  In H. W. Reese & L. P. Lipsitt (Eds.),
    	   Advances in Child Development and Behavior, pp. 61-116.  New
    	   York: Academic Press
    	2. Langley,P. (1987).  A General Theory of Discrimination
    	   Learning.  In D. Klahr, P. Langley, & R. Neches (Eds.),
    	   Production System Models of Learning and Development, pp.
    	   99-161. Cambridge, MA: MIT Press
    	3. Newell, A. (1990).  Unified Theories of Cognition.
    	   Cambridge, MA: Harvard University Press
    	4. McClelland, J.L. (1988).  Parallel Distibuted Processing:
    	   Implications for Cognition and Development.  Technical
    	   Report AIP-47, Department of Psychology, Carnegie-Mellon
    	   University
    	5. Shultz, T., Mareschal, D., & Schmidt, W. (1994).  Modeling
    	   Cognitive Development on Balance Scale Phenomena. Machine
    	   Learning, Vol. 16, pp. 59-88.

    4. Relevant Information:
    	This data set was generated to model psychological
    	experimental results.  Each example is classified as having the
    	balance scale tip to the right, tip to the left, or be
    	balanced.  The attributes are the left weight, the left
    	distance, the right weight, and the right distance.  The
    	correct way to find the class is the greater of
    	(left-distance * left-weight) and (right-distance *
    	right-weight).  If they are equal, it is balanced.

    5. Number of Instances: 625 (49 balanced, 288 left, 288 right)

    6. Number of Attributes: 4 (numeric) + class name = 5

    7. Attribute Information:
    	1. Class Name: 3 (L, B, R)
    	2. Left-Weight: 5 (1, 2, 3, 4, 5)
    	3. Left-Distance: 5 (1, 2, 3, 4, 5)
    	4. Right-Weight: 5 (1, 2, 3, 4, 5)
    	5. Right-Distance: 5 (1, 2, 3, 4, 5)

    8. Missing Attribute Values:
    	none

    9. Class Distribution:
       1. 46.08 percent are L
       2. 07.84 percent are B
       3. 46.08 percent are R