Khamooshi, H and Cioffi, D F (2013) Uncertainty in task duration and cost estimates: Fusion of probabilistic forecasts and deterministic scheduling. Journal of Construction Engineering and Management, 139(5), pp. 488-497. ISSN 0733-9364
Abstract
A model for project budgeting and scheduling with uncertainty is developed. The traditional critical-path method (CPM) misleads because there are few, if any, real-life deterministic situations for which CPM is a great match; program evaluation and review technique (PERT) has been seen to have its problems, too (e.g., merge bias, unavailability of data, difficulty of implementation by practitioners). A dual focus on the distributions of the possible errors in the time and cost estimates and on the reliability of the estimates used as planned values suggests an approach for developing reliable schedules and budgets with buffers for time and cost. This method for budgeting and scheduling is executed through either simulation or a simple analytical approximation. The dynamic buffers provide much-needed flexibility, accounting for the errors in cost and duration estimates associated with planning any real project, thus providing a realistic, practical, and dynamic approach to planning and scheduling.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | budget; contingency; cost; estimate; probability; project management; reliability; scheduling; simulation |
| Index terms: | scheduling, budgeting, bias, practitioner, accounting, project budgeting, programme evaluation and review technique, buffer, planned value, cost estimate, duration, estimate, implementation, project management |
| Subjects: | operations research, contractual arrangements, economic analysis, cost planning, financial and cost management, practitioner, project controls, financial management, financial risk, project management theory and practice, probability and distributions |
| Topics: | Time Control, Cost Management, Business Strategy, Project Management, Research Practice, Roles and Professions, Procurement |
| Descriptive scope: | 3 PCA |
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