Acquisition and performance as a function of uncertainty and structure in serial tracking tasks

Criterion performance and response organization were evaluated in skilled tasks involving the pursuit tracking of step-function inputs. Both the structure and degree of first-order sequential dependencies among target events were manipulated in a factorial design. Tracking error was found to be a function of the degree of uncertainty and of the task structure (one vs two low-probability sequential alternatives) and the latter could not be attributed to the degree of uncertainty, per se. Furthermore, detailed analysis of continuous response records revealed differences in response strategies as a function of task structure. These differences accounted, in part, for difference in tracking performance and discrepancies between the present and prior research.