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Realism in Assessment of Effort Estimation Uncertainty: It Matters How You Ask
April 2004 (vol. 30 no. 4)
pp. 209-217
Traditionally, software professionals are requested to provide minimum-maximum intervals to indicate the uncertainty of their effort estimates. In this paper, we claim that the traditional request is not optimal and leads to overoptimistic views about the level of estimation uncertainty. Instead, we propose that it is better to frame the request for uncertainty assessment: "How likely is it that the actual effort will be more than/less than X?” Our claim is based on the results of a previously reported experiment and field studies in two companies. The two software companies were instructed to apply the traditional and our alternative, framing on random samples of their projects. In total, we collected information about 47 projects applying the traditional framing and 23 projects applying the alternative framing.

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Index Terms:
Cost estimation, risk management, software psychology.
Magne J?rgensen, "Realism in Assessment of Effort Estimation Uncertainty: It Matters How You Ask," IEEE Transactions on Software Engineering, vol. 30, no. 4, pp. 209-217, April 2004, doi:10.1109/TSE.2004.1274041
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