Abstract

The effect of experience with a preceding task on the accuracy of predictions of duration was examined in three experiments, where two tasks comprising similar or different mental operators were performed consecutively. Results supported an anchoring account of misestimation, which states that misestimation occurs because predictions are anchored to the duration of the preceding task. Preceding performance of a longer task led to overestimation on a shorter task with similar mental operators (Experiment 1), whereas preceding performance of a shorter task comprising similar or different mental operators led to underestimation on a longer task Experiments 1 to 3). Contrary to the planning fallacy account (Kahneman & Tversky, 1979), these findings indicate that preceding task performance is considered when predicting duration, but that using such information does not necessarily improve accuracy.