Predicting the Effect of Longitudinal Variables on Cost and Schedule Performance

<p>Determining accurate cost and schedule is a crucial step to planning acquisition expenditures but history has shown that estimates are routinely low. Several researchers have attempted to forecast cost and schedule growth; we pick up this stream of research with a new approach. Our data collection and analysis focused on bringing in new data sources and added longitudinal variables to account for changes that took place over time. We assessed cost and schedule parameters for 37 major acquisition programs between Milestones II and III resulting in 172 input variables and 5 regression models 2 for schedule slippage and 3 for cost growth. All five models passed statistical scrutiny and exhibited an Adjusted r2 in excess of 0.80. The primary discriminator was the inclusion of strictly qualitative variables taken from Selected Acquisition Report narratives and change justifications. We called these soft variables and coded them on a scale of 1 to 5 in the categories of funding problems political problems technical challenges and contractor cost growth. Models with and without soft variables are presented to demonstrate their relative benefit. Finally implications and implementation examples provide users a path to what-if analysis and decision-making.</p><p>This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact and remains as true to the original work as possible. Therefore you will see the original copyright references library stamps (as most of these works have been housed in our most important libraries around the world) and other notations in the work.</p><p>This work is in the public domain in the United States of America and possibly other nations. Within the United States you may freely copy and distribute this work as no entity (individual or corporate) has a copyright on the body of the work.</p><p>As a reproduction of a historical artifact this work may contain missing or blurred pages poor pictures errant marks etc. Scholars believe and we concur that this work is important enough to be preserved reproduced and made generally available to the public. We appreciate your support of the preservation process and thank you for being an important part of keeping this knowledge alive and relevant.</p>