links for 2009-06-27

• ScienceDirect - Journal of Systems and Software : Better sure than safe? Over-confidence in judgement based software development effort prediction intervals
  "The uncertainty of a software development effort estimate can be indicated through a prediction interval (PI), i.e., the estimated minimum and maximum effort corresponding to a specific confidence level. For example, a project manager may be “90% confident” or believe that is it “very likely” that the effort required to complete a project will be between 8000 and 12,000 work-hours. This paper describes results from four studies (Studies A–D) on human judgement (expert) based PIs of software development effort. Study A examines the accuracy of the PIs in real software projects. The results suggest that the PIs were generally much too narrow to reflect the chosen level of confidence, i.e., that there was a strong over-confidence."
  (tags: psychology planning future)
• Roger Buehler | Psychology | WLU
  Bibliography of Roger Buehler.
  (tags: planning future psychology)
• Biases and Fallacies, Memories and Predictions: Comment on Roy, Christenfeld, and McKenzie (2005)
  Planning, personality, and prediction
  (tags: psychology future)
• Planning, personality, and prediction: The role of future focus in optimistic time predictions
  "The present studies examined cognitive processes underlying the tendency to underestimate project completion times. Two experiments tested the hypothesis that people generate overly optimistic predictions, in part, because they focus narrowly on their future plans for the target task and thus neglect other useful sources of information. Consistent with the hypothesis, instructing participants to adopt a ''future focus''-in which they generated concrete, specific plans for the task at hand-led them to make more optimistic predictions about when they would complete their intended Christmas shopping (Study 1) and major school assignments (Study 2). The future focus manipulation did not have a corresponding effect on actual completion times, and thus increased the degree of optimistic bias in prediction. The studies also demonstrated that the optimistic prediction bias generalized across different task domains, relevant individual differences... and other contextual variations."
  (tags: future planning psychology)