Personal interviewing is most efective when all the people to be interviewed are located i

n a relatively small geographical area, Otherwise. the time and expense spent in travelling from one person to anotber makes this type of interviewing economically impractical.Personal intervicwing is usunlly used when the information needed is too complex to be gathered by anotber technique. For example. a problem being studied may require the interviewer to probe beyond the more superficial (表面的) answers that might be obtained with another method, It is sometimes assumed that personal interviewing is the most accurate of all survey research techniques.Although personal interviewing may be accurate in many eases. human errors may prevent a researcher from obtaining valid results. Questions perceived by the interviewce(应试者)as an invasion of privacy ot threatening in any way will probably produce false or partially true answers. Also, since the interviewer must interpret the respondent&39;s statements. a certain amount of information loss results even though the respondent may be answering truthfully. In spite of the problems. At least two major advantages are provided by research technique. First, the alert interviewer can generally tell if the respondent is being truthful or if he or she is giving superficial or untrue responses. Second, the interviewer can rephrase questions, give more explanation, or probe more deeply if the initial questions do not produce the information desired. As a result, the information gleaned should be more accurate than that provided by interviews where no one is present to clarify questions or to interpret answers.

It can be concluded from the passage that when all the people to be interviewed are located in a relatively big geographical area____.

A.personal interviewing is most effective

B.personal interviewing is economically impractical

C.personal interviewing is the only technique to get information

D.telephone interviewing may not be used

Sometimes a researcher cannot get valid results because____.A.the information needed is too complex to be gathered

B.personal interviewing is the most accurate of all survey research techniques

C.personal interviewing is not as ffective as other research techniques

D.both interviewer and interviewee may make mistakes during the interviewing

In the second paragraph, the phrase“an invasion of privacy" most probably meansA.an unpleasant conversation

B.a challenge to interviewee’s professional skills

C.an interference with interviewee’s personal affairs

D.an interference with interviewee’s hobby

According to the last paragraph, one of the advantages of the personal interviewingA.the interviewer can ask the interviewee questions again in different ways

B.the interviewer can ask the interviewee some personal questions

C.the initial question do not produce the information desired

D.no one is present to clarify questions

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