APPROXIMATING CHAOTIC BEHAVIOR

Human subjects received feedback showing how closely their responses approximated the chaotic output of the logistic difference function. In Experiment 1, subjects generated analog responses by placing a pointer along a line. In Experiment 2, they generated digital responses in the form of three-digit numbers. In Experiment 3, feedback was sometimes provided and other times withheld. Responses came to approximate three defining characteristics of logistic chaos: Sequences were ''noisy,'' they were extremely sensitive to initial conditions, and lag 1 autocorrelation functions were parabolic in form. Chaos theory may describe some highly variable although precisely determined human behaviors.