Motivated underpinnings of the impact bias in affective forecasts.

Affective forecasters often exhibit an impact bias, overestimating the intensity and duration of their emotional reaction to future events. Researchers have long wondered whether the impact bias might confer some benefit. We suggest that affective forecasters may strategically overestimate the hedonic impact of events to motivate their production. We report the results of four experiments providing the first support for this hypothesis. The impact bias was greater for forecasters who had chosen which of two events to attempt to produce than for forecasters who had yet to choose (Experiment 1). The impact bias was greater when forecasts were made while forecasters could (or perceived they could) influence whether an event was produced than when its production had been determined but was unknown (Experiments 2A and 2B). Finally, experimentally manipulating the extremity of affective forecasts for an event influenced the amount of effort that forecasters expended to produce it (Experiment 3). The results suggest that the impact bias may not be solely cognitive in origin, but may also have motivated underpinnings.