Galaxy Charts: The 1,000-Light-Year View of the Data

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Galaxy Charts: The 1,000-Light-Year View of the Data

Journal of Cost Analysis and Parametrics

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This article presents a new kind of chart, called a Galaxy chart, which combines the strengths of other chart types. A Galaxy chart displays an entire Cost Element Structure on a single sheet of paper, showing all of the elements, their relationships, and their costs in a visually appealing way. Each child cost element is in orbit around its parent, with its children in orbit around their parent. The size of each cost element is directly proportional to its magnitude. Galaxy charts provide many insights. For instance, a single Galaxy chart displays the cost element structure hierarchy, the most significant cost elements, the least significant cost elements, the descending order of cost elements, and cost elements of equal value. This article will give an overview of the Galaxy chart concept, explain how to construct one, and explain a few of the insights that are available from the display insights that are typically difficult to gain without using a Galaxy chart.


Robert Nehring is a cost analyst for Technomics, where he has been involved on many projects throughout the Department of Defense, including the Army, Navy, Coast Guard, and Marine Corps. Early in his career, Mr. Nehring supported the Office of Naval Research by leading a project that analyzed and assessed the schedule and staffing projections for the Navys Littoral Combat Ship (LCS). Once joining Technomics, he has provided cost support to many programs, including LCS, Ohio Replacement Program, and the Offshore Patrol Cutter. Throughout his career, he has developed many innovative data visualization techniques, cost-related tools, and relational databases. In addition, he has been heavily involved in building both submarine and surface combatant performance-based cost models for the Navy. At the 2012 SCEA/ISPA Joint Annual Conference, he won Best Overall Paper for a paper about Galaxy charts. Mr. Nehring holds both undergraduate and graduate degrees in Industrial and Systems Engineering from Virginia Tech and is a SCEA-Certified Cost Estimator/Analyst (CCEA).

Katharine Mann is a cost analyst for Technomics, Inc., where she has been involved in projects throughout the Department of Defense. During her career, she has supported the Deputy Assistant Secretary of the Army-Cost & Economics (DASA-CE), Naval Sea Systems Command (NAVSEA), Naval Surface Warfare Center–Carderock, and the Coast Guard and Defense Acquisition University (DAU). Ms. Mann’s experience supporting these customers includes applied cost analysis and research, relational database maintenance, developing and enhancing an analogy model using non-recurring engineering data, data visualization techniques, and assisting with training modules on software cost estimating. At the 2012 SCEA/ISPA Joint Annual Conference, she was a co-author on the Best Overall Paper about Galaxy charts. Ms. Mann holds both Bachelors and Masters of Science degrees in Industrial and Systems Engineering from Virginia Tech as well as a graduate certificate in Engineering Education and is a member of SCEA.

Robert Jones graduated from the University of Rhode Island with a Bachelor’s degree in Mechanical Engineering in 1969, and he received a Master’s degree in Mechanical Engineering from the Catholic University of America in 1973. For 33 years he was employed by the Navy at the NSWC Carderock Division. Upon retirement in January 2003, he was the Department Head of the Systems Engineering and Analysis Department. Since 2003, he has been a Senior Cost Analyst with Technomics, Inc. He has more than 30 years of experience in life cycle cost estimating and economic analysis of high technology military systems. His areas of emphasis are: collecting, organizing, managing, and analyzing cost and technical databases; creating engineering build-up, parametric, and analogy-based cost models for hardware and software systems; supporting ACAT I program offices with regard to Analysis of Alternatives (AoA), Program Life Cycle Cost Estimates, Independent Cost Estimates, Earned Value Management (EVM) analysis, source selection participation, and preparation of Contractor Cost and Software Data Reporting plans. He made presentations to DoDCAS, DoNCAS, SCEA, and ISPA. At the 2012 SCEA/ISPA Joint Annual Conference, he won Best Overall Paper for a paper about Galaxy charts.