An experimental study of adaptation level theory in the comparative judgments of lifted weights

Abstract

Helson's Adaptation-Level (AL) theory formulated the background-effects on judgment according to the notion of behavioral relativity. The purpos of this experimental study is to apply Helson's weighted geometric mean AL-model to the experiment of lifted weights by means of comparative judgment. A more general AL formula, a deduction from this AL formula to experimental model, and the method of estimating parameters by the method of least squares were stated.
The main results of this experiment were as follows;
(1) Agreement between theoretical AL-model and experimental data was excellent. AL theory gives a good account of comparative judgment data. Goodness of fit to the data of each subject is more excellent.
(2) There is a distinction between standard stimulus effects and anchor stimulus effects on judgment.
(3) Least squares estimate of relative weight of standard stimulus was 0.856. An individual effect constant affecting judgments was 139.8g.
(4) Legitimacy of logarithmic law as a psychophysical function seems to require further reexperimentation.