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Survey modes and response effects: Overview and introduction U. Engel 3. Survey mode and mode effects E.D. De Leeuw, J.J. Hox 4. Interviewers and survey error: Overview and introduction P. Sturgis 7.
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.