Abstract
An important question about individual differences in the exponent of the psychophysical power law is how they should be interpreted. The differences may reflect permanent characteristics of individuals, and it has been argued that, if this is so, the range of these differences is so great as to identify the class of data as exceptional among the physical and biological sciences. Cited as evidence of such permanence has been the correlation between individual exponents obtained on two separate occasions. In a previous paper, we showed that increasing the time interval between occasions reduced the correlation to a nonsignificant level; we argued, therefore, that obtained individual differences in exponents, even though large, depended upon the operation of factors only incidentally associated with the particular observer. In a series of new studies of session-to-session correlation between individual exponents, we provide evidence that: (1) our original finding for magnitude estimates of visual size is repeatable, with the correlation dropping to nearly zero after 1 week; (2) when judged line length is matched to brightness, a delay of I week is sufficient to produce a nonsignificant correlation; (3) in contrast, magnitude estimates of loudness yield significant correlations after a week’s delay; (4) but, when moduli are arbitrarily changed between sessions by the experimenter, these correlations for magnitude estimates of loudness drop to a nonsignificant level, even for a zero-delay condition. We conclude that, whereas in some scaling tasks the passage of time alone between sessions is sufficient to disrupt what appears to be the mnemonic basis for session-to-session correlation, in other (less familiar) tasks, more positive interference (in the form of a modulus change) is needed to achieve the same end. The evidence is consistent with the belief that enduring characteristics of the observer contribute only a small portion of the variability in individual power law exponents.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Cain, W. S. Differential sensitivity for smell: “Noise” at the nose.Science, 1977,195, 796–798.
Cross, D. V. Sequential dependencies and regression in psychophysical judgments.Perception & Psychophysics, 1973,14, 547–552.
Curtis, D. W., Attneave, F., &Harrington, T. L. A test of a two-stage model of magnitude judgment.Perception & Psychophysics, 1968,3, 25–31.
Ekman, G., Hosman, B., Lindman, R., Ljungberg, L., &Akesson, C. Interindividual differences in scaling performance.Perceptual and Motor Skills, 1968,26, 815–823.
Engelund, W., &Dawson, W. E. Individual differences in power functions for a 1-week intersession interval.Perception & Psychophysics, 1974,15, 349–352.
Engen, T., &Ross, B. M. Effect of reference number on magnitude estimation.Perception & Psychophysics, 1966,1, 74–76.
Green, D. M., &Luce, R. D. Variability of magnitude estimates: A timing theory analysis.Perception & Psychophysics, 1974,15, 291–300.
Green, D. M., Luce, R. D., &Duncan, J. E. Variability and sequential effects in magnitude production and estimation of auditory intensity.Perception & Psychophysics, 1977,22, 450–456.
Hellman, R. P. Stability of individual loudness functions obtained by magnitude estimation and production.Perception & Psychophysics, 1981,19, 63–70.
Jesteadt, W., Luce, R. D., &Green, D. M. Sequential effects in judgments of loudness.Journal of Experimental Psychology: Human Perception and Performance, 1977,3, 92–104.
Jones, F. N., &Marcus, M. J. The subject effect in judgments of subjective magnitude.Journal of Experimental Psychology, 1961,61, 40–44.
Jones, F. N., &Woskow, M. On the relationship between estimates of magnitude of loudness and pitch.American Journal of Psychology, 1962,75, 669–671.
King, M. C., &Lockhead, G. R. Response scales and sequential effects in judgment.Perception & Psychophysics, 1981,30, 599–603.
Logue, A. W. Individual differences in magnitude estimation of loudness.Perception & Psychophysics, 1976,19, 279–280.
Luce, R. D. What sort of measurement is psychophysical measurement?American Psychologist, 1972,17, 96–106.
Luce, R. D., &Mo, S. S. Magnitude estimation of heaviness and loudness by individual subjects.British Journal of Mathematical Statistical Psychology, 1965,18, 159–174.
Marks, L. W.Sensory processes: The new psychophysics. New York: Academic Press, 1974.
Mitchell, J. J., &Gregson, R. A. M. Between-subject variation and within-subject consistency of olfactory intensity scaling.Journal of Experimental Psychology, 1971,19, 314–318.
Rule, S. J., &Markley, R. P. Subject differences in crossmodality matching.Perception & Psychophysics, 1971,9, ll5–1l7.
Stevens, S. S. Measurement and man.Science, 1958,127, 384–389.
Stevens, S. S. The psychophysics of sensory function.American Scientist, 1960,48, 226–253.
Stevens, S. S. Neural events and the psychophysical law.Science, 1970,170, 1043–1050.
Stevens, S. S. Perceived level of noise by Mark VII and decibels (E).Journal of the Acoustical Society of America, 1972,51, 575–601.
Stevens, S. S.Psychophysics: Introduction to its perceptual, neural, and social prospects (G. Stevens, Ed.), New York: Wiley, 1975.
Stevens, S. S., &Guirao, M. Subjective scaling of length and area and the matching of length to loudness and brightness.Journal of Experimental Psychology, 1963,66, 177–186.
Teghtsoonian, M. The judgment of size.American Journal of Psychology, 1965,71, 392–402.
Teghtsoonian, M., &Teghtsoonian, R. How repeatable are Stevens’ power law exponents for individual subjects?Perception & Psychophysics, 1971,10, 147–149.
Teghtsoonias, R. On the exponents in Stevens’ law and the constant in Ekman’s law.Psychological Review, 1971,78, 71–80.
Teghtsoonian, R., &Teghtsoonian, M. Range and regression effects in magnitude scaling.Perception & Psychophysics, 1978,24, 305–314.
Undeawood, B. J. Interference and forgetting.Psychological Review, 1957,24, 49–60.
Walsh, J. K., &Browman, C. P. Intraindividual consistency on a cross-modality matching task.Perception & Psychophysics, 1978,23, 210–214.
Wanschura, R. G., &Dawson, W. E. Regression effect and individual power functions over sessions.Journal of Experiraental Psychology, 1974,102, 806–812
Author information
Authors and Affiliations
Additional information
The research reported here was supported in part by Grant HD10857 and by Grant NS12597.
Rights and permissions
About this article
Cite this article
Teghtsoonian, M., Teghtsoonian, R. Consistency of individual exponents in cross-modal matching. Perception & Psychophysics 33, 203–214 (1983). https://doi.org/10.3758/BF03202857
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.3758/BF03202857