How long will it take? Power biases time predictions

Journal of Experimental Social Psychology (Impact Factor: 2.29). 07/2010; 46(4). DOI: 10.1016/j.jesp.2010.03.005


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.

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    • "One of the problems that makes time management (Koch and Kleinmann 2002) so difficult is the planning fallacy: the tendency to underestimate future task duration despite knowing that previous tasks overran (Kahneman and Tversky 1979). Considerable research (e.g., Buehler et al. 1997; Burt and Kemp 1994; Halkjelsvik et al. 2011; König 2005; Roy et al. 2008; Thomas et al. 2004; Weick and Guinote 2010; for recent overviews see Buehler et al. 2010, and Halkjelsvik and Jørgensen 2012) has almost universally found that tasks take longer than predicted, and this has been observed on various laboratory and real world tasks including writing college assignments (e.g., Buehler et al. 1994) and shopping for gifts (Kruger and Evans 2004). Such underestimation of task duration may cause serious problems; for example, students may start to work on assignments too late to achieve good grades and gifts bought in the rush may not have the anticipated consequences (see Kruger and Evans 2004). "
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    ABSTRACT: It is a common time management problem that people underestimate the duration of tasks, which has been termed the “planning fallacy.” To overcome this, it has been suggested that people should be informed about how long they previously worked on the same task. This study, however, tests whether previous misestimation also affects the duration estimation of a novel task, even if the feedback is only self-generated. To test this, two groups of participants performed two unrelated, laboratory-based tasks in succession. Learning was manipulated by permitting only the experimental group to retrospectively estimate the duration of the first task before predicting the duration of the second task. Results showed that the experimental group underestimated the duration of the second task less than the control group, which indicates a general kind of learning from previous misestimation. The findings imply that people could be trained to carefully observe how much they misestimate task duration in order to stimulate learning. The findings are discussed in relation to the anchoring account of task duration misestimation and the memory-bias account of the planning fallacy.
    Current psychology (New Brunswick, N.J.) 03/2015; 34:1-13. DOI:10.1007/s12144-014-9236-3 · 0.45 Impact Factor
    • "The three scales were also highly correlated (rs = 0.60 to 0.70), and may tap the same underlying construct: a desire for control or an actual feeling of control. Weick and Guinote (2010) found an effect of power on time predictions. "
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    ABSTRACT: Halkjelsvik, T., Rognaldsen, M. & Teigen, K. H. (2012). Desire for control and optimistic time predictions. Scandinavian Journal of Psychology 53, 499–505. Few studies have investigated individual differences in time predictions. We report two experiments that show an interaction between the personality trait Desirability of Control and reward conditions on predictions of performance time. When motivated to perform a task quickly, participants with a strong desire for control produced more optimistic predictions than those with a weaker desire for control. This effect could also be observed for a completely uncontrollable task. The results are discussed in relation to the finding that power produces more optimistic predictions, and extend this work by ruling out some previously suggested explanations.
    Scandinavian Journal of Psychology 10/2012; 53(6). DOI:10.1111/j.1467-9450.2012.00973.x · 1.29 Impact Factor
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    • "In the same vein, social power (primed with contextual cues) is associated with overoptimistic forecasts (Weick and Guinote, 2010). An alternative and non-exclusive point of view suggests that individuals refer to inaccurate memories. "
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    ABSTRACT: Introduction: According to Planning Fallacy, people underestimate the time required to complete a task. A review of the social, cognitive, and motivational factors that moderate Planning Fallacy suggests that variability in Web searching tasks would lead to an overestimation of retrieval time, at least when the task duration is short (about 10 minutes). Objective: The goals of this pilot study are twofold: to check the accuracy of forecasts when users estimate the time required to retrieve information on the Web, and to understand users' strategies for dealing with the Web for multipurpose documentation. Method: Participants (n = 32) were asked how long it would take to answer four encyclopedic questions on the Web; questions were in various fields with two levels of difficulty and two types of answers (qualitative vs quantitative). We compared estimations of the time required to retrieve specific information on the Web with the actual retrieval time. Forecasts were made before and after the effective retrieval task (within-subjects design). Results: A significant and large overestimation of the anticipated time was observed, especially for questions with a qualitative answer. The overestimation range was between 195% and 473% for mean search durations between 4.5 and 10.3 min. Task perceived difficulty was the best predictor of time anticipation (r 2 < 0.32). Web search self-efficacy and experience contributed slightly to the overestimation but only for easy questions. Conclusion: Overestimation of the time required to complete a Web searching task (i.e. pessimistic Planning Fallacy) results from a combination of factors: short length of tasks, variability in task difficulty, and the qualitative or quantitative nature of the correct answer. Search time forecast could be used as a benchmark to improve Web usability.
    Revue Européenne de Psychologie Appliquée 04/2012; Volume 62(Issue 2):Pages 103-109. DOI:10.1016/j.erap.2011.12.004 · 0.52 Impact Factor
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