Document Type
Article
Publication Date
Spring 2025
Abstract
This article analyzes and investigates the distribution of cost growth of the Estimate at Completion (EAC) for the Work Breakdown Structure (WBS) elements of approximately 60 historical United States Acquisition Category I Research, Development, Test and Evaluation aircraft programs. Using the method of maximum likelihood in conjunction with the Akaike Information Criterion, the authors suggest that both the lognormal and Weibull distributions provide relatively good fit to EAC cost growth, with the lognormal slightly edging out the Weibull. As a summarized finding, the authors present their empirical results for the mean, coefficient of variation (CV), the 15th and 85th percentiles by WBS element. With an overall mean of 1.36, 0.80, and 3.1 for the mean, CV, and 85th percentile, respectively, these results suggest a high likelihood of cost growth in budgets. To account for this possible underestimation, the authors propose higher cost factors to consider or to use as a crosscheck.
DOI
10.22594/dau.24-925.32.01
Source Publication
Defense Acquisition Research Journal
Recommended Citation
Marquis, K.P., White, E.D., Lucas, B.M., Fass, R.D., Ritschel, J.D., & Valentine, S.M. (2025). Distribution comparisons of EAC cost growth for aircraft work breakdown structure elements. Defense Acquisition Research Journal, 32(1), 30–53. https://doi.org/10.22594/dau.24-925.32.01
Included in
Aviation Commons, Finance and Financial Management Commons, Government Contracts Commons, Operations and Supply Chain Management Commons
Comments
Defense ARJ is published by the Defense Acquisition University. The journal's online version is hosted at https://www.dau.edu/library/darj