EMPLOYMENT PSYCHOLOGY 
gather significant information which can be used in pre- 
dicting 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 deter- 
mining whether or not the applicant should be accepted 
until after the importance of these facts has been well estab- 
lished. 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 statis- 
tical analysis of the answers to each question must be made 
in order to determine which of the facts covered are signifi- 
cant 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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