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By Richard Valliant, Jill A. Dever, Frauke Kreuter. Jill A. Dever, PhD, is Senior Research Statistician at RTI International in Washington, DC. She is founder of the International Program for Survey and Data Science and co-founder of the Coleridge Initiative.
When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.