THE PROBLEM OF SELECTION 
lation between test performance and success at the job is 
high, one may be used as the sign of the other. The test 
performance, requiring at most a few hours, then becomes 
a prognosis of what the applicant will be able to accomplish 
at the job over a long period of time. 
First are discussed the grounds for selecting a job or 
occupation to be studied in an organization, the analysis of 
this occupation, and the selection or construction of tests 
and other instruments of measurement; then, the technique 
of trying out the tests and determining their validity as 
indicators of probable success; while a final chapter deals 
with the installation and use of the new aids in selection. 
CHOICE OF JOB OR OCCUPATION TO BE STUDIED 
The range and variety of occupations inviting the atten- 
tion of the investigator is great. Care may well be exer- 
cised in deciding on the ones whose study by the scientific 
method gives most promise of valuable results. 
Not every occupation can profitably be made a subject of 
scientific study. This the investigator must realize if he 
wishes to avoid disappointment and failure. The scientific 
method requires the satisfaction of certain well-defined 
requirements. Where these conditions are absent, the in- 
vestigator must acknowledge that the scientific method can- 
not function. Other methods must suffice until conditions 
are made right for the introduction of scientific methods. 
Even where conditions permit the use of scientific proce- 
dure, economic considerations may not warrant such a study. 
Before deciding on an investigation of selection methods in 
an occupation, there is need of answers to these five ques- 
tions: 
1. Does a problem of selection actually exist in this occu- 
pation? Every scientific investigation aims to solve a prob- 
lem. It may happen that the problem here defines itself 
concretely in the form of excessive labor turnover, low pro- 
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