Date of Award


Document Type


Degree Name

Master of Science in Operations Research


Department of Operational Sciences

First Advisor

Raymond Hill, Jr., PhD.


The Air Force’s success is influenced by the manpower it has. The end-strength is Congressionally mandated. Predicting personnel retention is critical to the operations of the military. Over 10 years ago, the Air Force produced enlisted career field sustainment lines based on manning. If a career field was over manned the authorizations were decreased, likewise if a career field was under manned the authorizations were increased. The constant fluctuation of manning caused bathtubs to be created and requirements to go unfilled. Currently, the Air Force produces enlisted career field sustainment lines based on the 5-year historical retention rates. This method produced a more steady state approach, as well as providing a means to adjust the line for other policy actions such as retraining in/out. The need to have a statistically based approach is essential for explaining and defending the creation of the sustainment lines. Many decisions that affect the methods selected for maintaining end-strength are based off the sustainment lines. Data from 2006-2015 was utilized in this research. Logistic regression was used to determine if any significant variables existed, however logistic regression did not provide enough insight into the behavior of the data to be utilized. A survival analysis approach, using retention data, provides a statistically sound methodology to the creation of the sustainment lines. This study produces sustainment lines based on the survival functions for each enlisted career field. It also analyzes the potential of grouping the years of service to manage the career and analyzes retention based on gender and on marital status.

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