ABSTRACT
The accuracy of estimates is largely dependent on the quality of the estimating program and the experience of the estimator. Quality is also dependent on estimating labor and time. The relationship is not linear. Reasonable investments of time and resources will, usually, provide better cost estimates. Further improvements become increasingly expensive, with only modest improvements in accuracy resulting from substantial expenditures of time and resources. A point is soon reached where estimate quality is almost completely controlled by problems of forecasting future economic conditions, local project conditions, and quality of project performance. No significant improvement in estimate quality can be made thereafter, except by incorporation of actual design and cost information as the work develops. Often, senior management does not understand or prefers not to accept this reality and insists that a 10% quality be produced when the
requisite information is not available. Thus, many projects are funded/approved with an inadequate cost baseline.
