…include such assessments as the interview, rating scales, self-reports, personality inventories, projective techniques, and behavioral observation.

…research device is the panel interview—repeated interviewing, over a considerable period of time, of small sets of individuals considered more or less representative of the intended audiences. The object is to obtain (if possible, without their knowing it) a great deal of information about their life-styles, belief systems, value systems,…

Interviewing is another potential source of error. Inexperienced interviewers may bias their respondents’ answers by asking questions in inappropriate ways. They may even alienate or antagonize some respondents so that they refuse to complete the interview. Interviewers also sometimes fail to record the replies…

Patterns of responses to interview questions, once thought to be purely qualitative, have also been subject to mathematical scaling. A method devised by psychologist L.L. Thurstone in the late 1920s gained popular use in sociology. In this approach a list of items is presented to a number of judges…