1. Personal, Telephone and Mail Interviews

2. Methods of Data Collection Personal InterviewTelephone InterviewMail Survey

3. Personal Interview Characterized by interaction of Four Entities:  Researcher  Interviewer  Interviewee  Interview Environment

4. Personal Interview Methods  Door to Door Interviewing  Executive Interviewing  Mall Intercept Surveys  Self-Administered Interviews  Purchase Intercept Technique (PIT)  Omnibus Surveys

5. Personal Interviews (Advantages)  Can arouse and keep interest  Can build rapport  Ask complex questions with the help of visual and other aids  Clarify misunderstandings  High degree of flexibility  Probe for more complete answers

6. Personal Interviews (Advantages)  Good for neutral questions  Do not need an explicit or current list of households or individuals

7. Personal Interviews (Limitations)  Bias of Interviewer  Response Bias  Embarrassing/personal questions  Time Requirements  Cost Per Completed Interview Is High  Trained staff of interviewers geographically near the sample required

8. Telephone Interviewing  Selecting telephone numbers 1. Pre-specified list 2. A directory  Random dialing procedure 1. Random digit dialing 2. Systematic random digit dialing (SRDD) 3. Plus-one dialing

9. Telephone Interviewing (Advantages) Central location, under supervision, at own hours More interviews can be conducted in a given time Travelling time is saved Shorter data collection periods More hours of the day are productive

10. Telephone Interviewing (Advantages) Repeated call backs at lower cost (WATS) Absence of administrative costs Lower cost per completed interview Less sample bias due to no response Intrusiveness of the phone Ease of call backs

11. Telephone Interviewing (Limitations)  Inability to employ visual aids or complex tasks  Interviewer must rely solely on verbal cues to judge the reaction and understanding of respondents  Can't be longer than 5-10 min. or they get boring

12. Telephone Interviewing (Limitations)  Amount of data that can be collected is relatively less  A capable interviewer essential  Potential for sample bias  No phone, unlisted phone or mobile phones

13. Mail Surveys  Requires a broad identification of the individuals to be sampled before data collection begins Some Decisions That Need to Be Taken Are:  Type of Return Envelope  Postage  Method of Addressing

14. Mail Surveys  Cover Letter  The Questionnaire Length, Layout, Color, Format etc  Method of Notification  Incentive to Be Given

15. Mail Surveys (Advantages)  Lower cost  Better results, including a shorter response time  Reliable answers as no inhibiting intermediary  Survey answered at respondents’ discretion

16. Mail Surveys (Advantages)  Can be accomplished with minimal staff and facilities.  Provides access to widely dispersed samples.  Respondents have time to give thoughtful answers, look up records, or consult others.

17. Mail Surveys (Limitations) The identity of the respondent is inadequately controlled No control over whom the respondent consults before answering the questions The speed of the response can't be monitored No control on the order in which the questions are exposed and answered

18. Mail Surveys (Limitations)  Respondents’ understanding of the questions  The respondent may not clearly understand the question and has no opportunity to clarify  Cannot have long questionnaires  Subject to availability of a mailing list  Response rate is generally poor

19. Mail Surveys (Limitations)  Number of problems such as obsolescence, omissions, duplications, etc

20. Drop-off Questionnaire (Advantages)  The interviewer can explain the study, answer questions, and designate a respondent.  Response rates tend to be like those of personal interview studies.  There is more opportunity to give thoughtful answers and consult records.

21. Drop-off Questionnaire (Disadvantages)  Costs about as much as personal interviews.  A field staff is required.