How long will it take: Power biases time predictions

People tend to underestimate the time it takes to accomplish tasks. This bias known as the planning fallacy derives from the tendency to focus attention too narrowly on the envisaged goal and to ignore additional information that could make predictions more accurate and less biased. Drawing on recent research showing that power induces attentional focus, four studies tested the hypothesis that power strengthens the tendency to underestimate future task completion time. Across a range of task domains, and using multiple operationalizations of power, including actual control over outcomes (Study 1), priming (Studies 2 and 3), and individual differences (Study 4), power consistently led to more optimistic and less accurate time predictions. Support was found for the role of attentional focus as an underlying mechanism for those effects. Differences in optimism, self-efficacy, and mood did not contribute to the greater bias in powerful individuals' forecasts. We discuss the implications of these findings for institutional decision processes and occupational health.