Margaret R. Roller, MA, has been a research professional for 40 years. She is currently in private practice, where she works with some of the largest U.S. and global commercial and nonprofit organizations to find qualitative and quantitative research solutions. Ms. Roller has designed and conducted thousands of qualitative studies involving a wide assortment of methods, has presented and published numerous papers and articles on qualitative research design, and is the author of the widely read blog www.researchdesignreview.com. She serves on the exam development committee for the Marketing Research Association's Professional Researcher Certification.

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Paul J. Lavrakas, PhD, a research psychologist, serves as a senior methodological research consultant for several public and private sector organizations. He is also a Senior Fellow at the independent research organization NORC at the University of Chicago, and a Visiting Scholar at Northern Arizona University. Dr. Lavrakas has used quantitative and qualitative research methods extensively throughout his more than 40 years as an active research practitioner. Past president of the American Association for Public Opinion Research, he served as Vice President and chief methodologist for Nielsen Media Research and was on the faculties of Northwestern University and Ohio State University. His many publications include, most recently, the coedited volume Online Panel Research: A Data Quality Perspective.