Prescriptions for reducing the planning fallacy: the outside view versus unpacking

Siti Othman

Research output: ThesisDoctoral Thesis

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This thesis examines two theories of the planning fallacy, the inside / outside view and the unpacking approach, and extends planning fallacy explanations to projects involving Human Resource Information Systems (HRIS). This is the first empirical research to compare these theories on the same tasks and in the same study. The first study tested the two theories in a controlled experiment with 708 student participants working on small group project assignments. Individuals were nested within 162 project groups, and data was collected on a weekly basis for eight weeks. The hypotheses were tested using three-level hierarchical linear modeling (HLM). Both approaches showed opposite effects on predictions made towards completion time and outcome success, but had no effect on changes in confidence in predictions of completion time and outcome success. The second study explored whether the outside view, inside view or unpacking planning approaches are commonly used by planners for 45 real HRIS projects in organizations, and their effects on the accuracy of predictions about the success or failure of the project in terms of project completion time, outcome achieved, and satisfaction with the outcome. Hypotheses were tested using correlations, and results are also presented using descriptive statistics. The reported extent of use of the unpacking approach was positively related to the success of the project in terms of percentage of outcome achieved, the satisfaction with the HRIS system, which includes the content, format, accuracy, timeliness and ease of use of the system and the reported affective response towards outcome success. Recommendations for practice include support for the unpacking approach and the use of work breakdown structure in project planning. Suggestions are made for further research on differentiating the inside view and unpacking, and on the ii undesirable effects of both the outside view and unpacking in increasing rather than reducing
Original languageEnglish
QualificationDoctor of Philosophy
Publication statusUnpublished - 2009


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