Hostname: page-component-745bb68f8f-d8cs5 Total loading time: 0 Render date: 2025-01-08T10:04:23.278Z Has data issue: false hasContentIssue false

On Rotating to Smooth Functions

Published online by Cambridge University Press:  01 January 2025

James Arbuckle*
Affiliation:
Temple University
Michael L. Friendly
Affiliation:
York University
*
Requests for reprints should be sent to James Arbuckle, Department of Psychology, Temple University, Philadelphia, Pennsylvania 19122.

Abstract

Tucker has outlined an application of principal components analysis to a set of learning curves, for the purpose of identifying meaningful dimensions of individual differences in learning tasks. Since the principal components are defined in terms of a statistical criterion (maximum variance accounted for) rather than a substantive one, it is typically desirable to rotate the components to a more interpretable orientation. “Simple structure” is not a particularly appealing consideration for such a rotation; it is more reasonable to believe that any meaningful factor should form a (locally) smooth curve when the component loadings are plotted against trial number. Accordingly, this paper develops a procedure for transforming an arbitrary set of component reference curves to a new set which are mutually orthogonal and, subject to orthogonality, are as smooth as possible in a well defined (least squares) sense. Potential applications to learning data, electrophysiological responses, and growth data are indicated.

Type
Original Paper
Copyright
Copyright © 1977 The Psychometric Society

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

Portions of this research were supported by the National Research Council of Canada, Grant A8615 to the second author. We thank Jagdeth Sheth for supplying his raw data.

References

Reference Note

Carroll, J. D. & Chang, J. J. A general index of nonlinear correlation and its application to the problem of relating physical and psychological dimensions. Paper presented at the meeting of the American Psychological Association, Los Angeles, California, September, 1964.Google Scholar

References

Arbuckle, J. & Friendly, M. L. A program for rotation to smooth functions. Behavior Research Methods and Instrumentation, 1975, 7, 474474.CrossRefGoogle Scholar
Bock, R. D. Multivariate statistical methods in behavioral research, 1975, New York: McGraw-Hill.Google Scholar
Cleary, P. J. Description of individual differences in autonomic reactions. Psychological Bulletin, 1974, 81, 934944.CrossRefGoogle Scholar
Cliff, N. Adverbs multiply adjectives. Psychological Review, 1959, 66, 2744.CrossRefGoogle Scholar
Sheth, J. N. Using factor analysis to estimate parameters. Journal of the American Statistical Association, 1969, 64, 808822.CrossRefGoogle Scholar
Tucker, L. R. Determination of parameters of a functional relationship by factor analysis. Psychometrika, 1958, 23, 1923.CrossRefGoogle Scholar
Tucker, L. R. Learning theory and multivariate experiment: Illustration by determination of generalized learning curves. In Cattell, R. B. (Eds.), Handbook of multivariate experimental psychology, 1966, Chicago: Rand McNally.Google Scholar
Weitzman, R. A. A factor analytic method for investigating differences between groups of individual learning curves. Psychometrika, 1963, 28, 6980.CrossRefGoogle Scholar