Velocity-Time Estimation as a Function of Target Speed and Concealment Extent

Abstract

Eighteen subjects performed a velocity judgment task in which a target was displayed briefly and then disappeared from view. The subjects were required to estimate the time taken by the target to reach a final goal position. When the time data were converted to velocity estimates (concealment distance divided by concealment time estimate), a linear relationship between the mean and standard deviation of the estimated velocity was observed. A greater magnitude of error was associated with the slow target speeds than with the fast speeds, and with the long rather than the short concealment distances. Two distinct response patterns were evident when constant error was used as the time error measure. Some subjects responded with increasing negative constant error to decreases in target speed and increases in concealment distance, while other subjects responded to the same conditions with increased positive constant error. Differential perceptual responses to differences in task difficulty are proposed to account for these results.