1. Department of Health Administration and Policy, College of Health and Human Services, George Mason University , Fairfax, VA , USA
2. Department of Statistics, Volgenau School of Engineering, George Mason University , Fairfax, VA , USA
3. Department of Psychology and the Center for the Study of Tobacco Products, Virginia Commonwealth University , Richmond, VA , USA
4. Department of Health Behavior and Policy, School of Medicine, Virginia Commonwealth University , Richmond, VA , USA
5. Department of Geography and Geoinformation Science, College of Science, George Mason University , Fairfax, VA , USA