Time estimation methods--do they influence prospective duration estimates?

The validity of an attentional model of prospective time estimation was tested in three experiments. In the first experiment two variables were manipulated: (1) nontemporal information processing load during the estimated interval, and (2) time estimation method, ie production of time simultaneously with the performance of a second task, or reproduction of time immediately upon termination of a task whose duration has to be measured. As predicted, a positive relationship between produced time length and information processing load demanded by a simultaneous task, and a negative relationship between reproduced time length and information processing load during the estimated interval, were found. The results were replicated in a second experiment in which verbal estimates of time were also measured and the objective duration of the estimated interval was varied. The pattern of results obtained for verbal estimates was similar to that obtained for reproduced ones. The results of a third experiment indicated that produced and reproduced times were positively correlated with clock time. The results are interpreted as supporting an attentional model of prospective time estimation.