Data Collection in the Field, Nonresponse

Error, and Questionnaire Screening

Ch 14 2

Nonsampling Error in Marketing Research

• Nonsampling error includes

– All types of nonresponse error

– Data gathering errors

– Data handling errors

– Data analysis errors

– Interpretation errors

Ch 14 3

Possible Errors in Field Data Collection

• Field worker error: errors committed by the persons who administer the questionnaires

• Respondent error: errors committed on the part of the respondent

• Errors may be either intentional or unintentional.

Ch 14 4

Data Collection Errors

Ch 14 5

Possible Errors in Field Data Collection: Field-Worker Errors

• Intentional field worker error: errors committed when a data collection person willfully violates the data collection requirements set forth by the researcher– Interviewer cheating occurs when the

interviewer intentionally misrepresents respondents

– Leading respondents occurs when the interviewer influences respondent’s answers through wording, voice inflection, or body language

Ch 14 6

Possible Errors in Field Data Collection: Field-Worker Errors

• Unintentional field worker error: errors committed when an interviewer believes he or she is performing correctly– Interviewer personal characteristics

occurs because of the interviewer’s personal characteristics such as accent, sex, and demeanor

Ch 14 7

Possible Errors in Field Data Collection: Field-Worker Errors

– Interviewer misunderstanding occurs when the interviewer believes he or she knows how to administer a survey but instead does it incorrectly

– Fatigue-related mistakes occur when interviewer becomes tired

Ch 14 8

Possible Errors in Field Data Collection: Respondent Errors

• Intentional respondent error: errors committed when there are respondents that willfully misrepresent themselves in surveys– Falsehoods occur when respondents

fail to tell the truth in surveys– Nonresponse occurs when the

prospective respondent fails to take part in a survey or to answer specific questions on the survey

Ch 14 9

Possible Errors in Field Data Collection: Respondent Errors

• Unintentional respondent error: errors committed when a respondent gives a response that is not valid but that he or she believes is the truth– Respondent misunderstanding occurs

when a respondent gives an answer without comprehending the question and/or the accompanying instructions

– Guessing occurs when a respondent gives an answer when he or she is uncertain of its accuracy

Ch 14 10

Possible Errors in Field Data Collection: Respondent Errors– Attention loss occurs when a

respondent’s interest in the survey wanes

– Distractions (such as interruptions) may occur while questionnaire administration takes place

– Fatigue occurs when a respondent becomes tired of participating in a survey

Ch 14 11

How to Control Data Collection Errors: Fieldworkers

Ch 14 12

How to Control Data Collection Errors: Respondents

Ch 14 13

How to Control Data Collection Errors: Respondents

Ch 14 14

Data Collection Errors with Online Surveys

• Multiple submissions by the same respondent

• Bogus respondents and/or responses

• Misrepresentation of the population

Ch 14 15

Nonresponse Error

• Nonresponse: failure on the part of a prospective respondent to take part in a survey or to answer specific questions on the survey– Refusals to participate in survey– Break-offs during the interview– Refusals to answer certain

questions (item omissions)• Completed interview must be defined

Ch 14 16

Nonresponse Error

• Response rate enumerates the percentage of the total sample with which the interviews were completed

Ch 14 17

Nonresponse Error

• CASRO response rate formula:

Ch 14 18

Reducing Nonresponse Error

• Mail surveys:

– Advance notification

– Monetary incentives

– Follow-up mailings

• Telephone surveys:

– Callback attempts

Ch 14 19

Preliminary Questionnaire Screening

• Unsystematic and systematic checks of completed questionnaires

• What to look for in questionnaire inspection

• Incomplete questionnaires• Nonresponses to specific questions

(item omissions)• Yea- or nay-saying patterns• Middle-of-the-road patterns

Ch 14 20

Unreliable Responses

• Unreliable responses are found when conducting questionnaire screening, and an inconsistent or unreliable respondent may need to be eliminated from the sample.

Ch 14 21

Minimizing Non-Sampling Error

• Cannot eliminate and cannot measure (except for non-response error)

• Implement CONTROLS to minimize error:

– Close supervision of data collectors

– Training

Ch 14 22

Minimizing Non-Sampling Error

– Care in constructing questionnaire and instructions…pretest!

– Provide incentives to respondents

– VALIDATION…industry standard is 10%