Comment on the following field situations, making recommendations for corrective action.
a. One of the interviewers has an excessive rate of refusals in in-home personal interviewing.
b. In a CATI situation, many phone numbers are giving a busy signal during the first dialing attempt.
c. An interviewer reports that, at the end of the interviews, many respondents asked if they had answered the questions correctly.
d. While validating the fieldwork, a respondent reports that she cannot remember being interviewed over the telephone, but the interviewer insists that the interview was conducted.