Editing Survey methodology (section)

==Interviewer effects==
Survey methodologists have devoted much effort to determining the extent to which interviewee responses are affected by physical characteristics of the interviewer. Main interviewer traits that have been demonstrated to influence survey responses are race,<ref>{{cite journal|first1=M.E|last1=Hill|title= Race of the interviewer and perception of skin color: Evidence from the multi-city study of urban inequality |journal=American Sociological Review|year=2002|volume=67|issue=1|pages=99–108|jstor=3088935|doi=10.2307/3088935}}</ref> gender,<ref>{{cite journal|first1=F.|last1=Flores-Macias|first2=C.|last2=Lawson|title=Effects of interviewer gender on survey responses: Findings from a household survey in Mexico|journal=International Journal of Public Opinion Research|year=2008|volume=20|issue=1|pages=100–110|doi= 10.1093/ijpor/edn007|s2cid=33820854|url=http://pdfs.semanticscholar.org/e13c/17fd3b3ecad084b6f120177cd9af1040e487.pdf|archive-url=https://web.archive.org/web/20190307134111/http://pdfs.semanticscholar.org/e13c/17fd3b3ecad084b6f120177cd9af1040e487.pdf|url-status=dead|archive-date=2019-03-07}}</ref>
and relative body weight (BMI).<ref>{{cite journal|first1=R.|last1=Eisinga|first2=M.|last2=Te Grotenhuis|first3=J.K.|last3=Larsen|first4=B.|last4=Pelzer|first5=T.|last5=Van Strien|title=BMI of interviewer effects|journal= International Journal of Public Opinion Research|year=2011|volume=23|issue=4|pages=530–543|doi=10.1093/ijpor/edr026|hdl=2066/99794|hdl-access=free}}</ref>
These interviewer effects are particularly operant when questions are related to the interviewer trait. Hence, race of interviewer has been shown to affect responses to measures regarding racial attitudes,<ref>{{cite journal|first1=B.A.|last1=Anderson|first2=B.D.|last2=Silver|first3=P.R.|title=The effects of the race of the interviewer on race-related attitudes of black respondents in SRC/CPS national election studies |journal= Public Opinion Quarterly |year=1988|volume=52|issue=3|pages=1–28|doi=10.1086/269108|last3=Abramson}}</ref>
interviewer sex responses to questions involving gender issues,<ref>{{cite journal|first1=E.W.|last1=Kane|first2=L.J.|last2=MacAulay|title= Interviewer gender and gender attitudes|journal= Public Opinion Quarterly |year=1993|volume=57|issue=1|pages=1–28|doi=10.1086/269352}}</ref>
and interviewer BMI answers to eating and dieting-related questions.<ref>{{cite journal|first1=R.|last1=Eisinga|first2=M.|last2=Te Grotenhuis|first3=J.K.|last3=Larsen|first4=B.|last4=Pelzer|title= Interviewer BMI effects on under- and over-reporting of restrained eating. Evidence from a national Dutch face-to-face survey and a postal follow-up |journal= International Journal of Public Health|year=2011|volume=57|issue=3|pages=643–647|doi= 10.1007/s00038-011-0323-z|pmid=22116390|pmc=3359459}}</ref>
While interviewer effects have been investigated mainly for face-to-face surveys, they have also been shown to exist for interview modes with no visual contact, such as telephone surveys and in video-enhanced web surveys. The explanation typically provided for interviewer effects is [[social desirability bias]]: survey participants may attempt to project a positive self-image in an effort to conform to the norms they attribute to the interviewer asking questions. Interviewer effects are one example [[survey response effects]].