1. dr PETER MARTIN CITY UNIVERSITY of LONDON Podejście mieszane (mixed mode) – możliwości i ograniczenia VI KONFERENCJA EWALUACYJNA WARSZAWA, 13-14.12.2010

2. www.europeansocialsurvey.org Overview Why Mixed Modes? Varieties of Mixed Mode Surveys Mixed Mode Designs: Sequential versus Concurrent Designs Limitations: Measurement errors, and how to reduce them Conclusion

3. www.europeansocialsurvey.org Survey Modes and their characteristics

4. www.europeansocialsurvey.org Varieties of Mixed-Mode Surveys Mixed mode survey systems Modes of contact with respondent Modes of data collection Mixed mode data collection Mixing modes within an interview: same respondent, different modes Mixing modes across interviews: different modes for different respondents This is what I am talking about.

5. www.europeansocialsurvey.org Mixed Mode Survey Designs: sequential Idea: Offer the cheapest mode first, the next cheapest second, and the most expensive mode last Example: American Community Survey 1.Postal questionnaires 2.Telephone interviews 3.Face-to-face interviews

6. www.europeansocialsurvey.org Mixed Mode Survey Designs: Concurrent Idea: Give respondents a choice of mode But: there is no evidence that freedom of choice increases the motivation to participate!

7. www.europeansocialsurvey.org Survey modes: implications for measurement effects

8. www.europeansocialsurvey.org Limitations of mixed mode surveys: Measurement effects Sensory Channel: Hearing: recency effects Sight: primacy effects Privacy and trust: social desirability bias Respondent motivation and task difficulty Satisficing

9. www.europeansocialsurvey.org Measurement effects: primacy and recency. A long list question

10. www.europeansocialsurvey.org Social desirability bias Large bias (poor quality) Small bias (good quality) Telephone Interviews Face-to-face Interviews Self-completion questionnaires (post or web)

11. www.europeansocialsurvey.org Questionnaire design: unified mode & mode-specific design (after Dillman et al., 2009, p. 326)

12. www.europeansocialsurvey.org Conclusions Mixing modes can save costs and yield high response rates But it is not an easy solution: mixed mode studies must be carefully designed. A mixed mode survey must have: A good plan for following up non-respondents (to encourage high response rates) Careful question and questionnaire design (to reduce measurement effects)

13. www.europeansocialsurvey.org Peter Martin Centre for Comparative Social Surveys, London p.martin@city.ac.uk Thank you !