Anchoring in Project Duration Estimation

The success of a business project often relies on the accuracy of its project duration estimates. Inaccurate and overoptimistic project schedules can result in significant project failures. In this paper, we explore whether the presence of anchors, such as relatively uninformed suggestions or expectations of the duration of project tasks, play a role in the project estimating and planning process. We conduct a controlled laboratory experiment to test the effect of anchors on task duration estimates. We find strong anchoring effects and systematic estimation biases that do not vanish even after the task is repeatedly estimated and performed. We also find that such persisting biases can be caused by not only externally provided anchors, but also by the planner’s own initial task duration estimate.

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