John F. Kros, PhD, is a professor of marketing?and supply chain management in the College of Business at East Carolina University in Greenville, North Carolina.?He also is the coauthor of Statistics for Health Care Professionals: Working with Excel.

Evelyn C. Brown, PhD, is a professor in the Department of Engineering and Associate Dean for Research in the College of Technology and Computer Science at East Carolina University, Greenville, North Carolina.