ABSTRACT
P. M. Fitts’ model of movement time used an information metric. This metric is very useful for characterizing the noise properties of a communication channel. A complete theory of movement must address both noise or information and dynamics or the mechanics of motion. R. A. Schmidt and his colleagues addressed the issue of dynamics and variability head on. Consistent with Schmidt’s Law, D. E. Meyer et al.’s optimization model assumes that the variability for each submovement is proportional to its average velocity. The optimal control metaphor, like the servomechanism metaphor, views movement as a control problem. Key parameters of the optimization model are the maximum number of submovements and the velocity of individual submovements. Meyer et al.’s, and John M. Flach et al.’s models and R. S. Shaw’s dripping faucet analysis consider the conjunction of stochastic and dynamic constraints. The dripping faucet metaphor was adapted from the literature on nonlinear dynamics.
