Improving conceptual cost estimating performance

Abstract

Conceptual cost estimates are fundamental inputs for the initial decision-making processes of construction projects. This paper has presented a methodology for assessing the expected accuracy and reliability of conceptual estimates. In doing that, a review of the basic concepts and definition of accuracy and reliability was presented along with a discussion of the importance of this information for decision making. A summary description of current practices demonstrated that there exist some approaches to this problem that are based only on information availability, without taking into account other important qualitative variables. A methodology based on experts' judgments and using the accuracy model was conceptualized. Using this methodology, estimators can have a knowledgeable assessment of the expected accuracy and reliability of a conceptual estimate that can be used for decision making at the conceptual stage of a project and also, to improve this important function