EMPLOYMENT PSYCHOLOGY
gather significant information which can be used in predicting
 the worker’s probable success or failure in a job.
(Other important functions of the interview are discussed
in Chapter XIX.) Rating scales and questionnaires serve
to focus the interviewer’s attention on essential data and to
provide the means of recording these data. Ideally, no facts
or figures derived from the interview should be used in determining
 whether or not the applicant should be accepted
until after the importance of these facts has been well established.
 These remarks apply as well to facts obtained from
the applicant’s references.
When questionnaires covering all types of information
desired by the investigator have been prepared and data
obtained from the group of workers being studied, a statistical
 analysis of the answers to each question must be made
in order to determine which of the facts covered are significant
 enough in this case to be useful in the selection of
applicants. But before plunging into the mathematical
procedures required in validating the questionnaires and
other examinations, we shall devote a chapter to questions
connected with their administration.

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