THE EXAMINATIONS AT WORK 2+; 
applied; therefore, some who fail technically in the tests 
may prove to be successful when hired under improved job 
conditions. Maximum value can be attached to test scores 
only so long as the conditions under which the applicants 
are employed with the use of tests reproduce in general the 
conditions under which they were employed when the tests 
were evaluated. 
As the type of applicant changes, the test standards may 
have to vary. Standards will also shift in accordance with 
changes in the demand for workers and the available supply. 
Variations in incentives due to changing economic pressure 
may invalidate some test norms. 
If men pass the tests and at a later date leave the company 
or are discharged, the reasons for leaving should be exam- 
ined critically to see whether the test predictions were really 
at fault. 
The investigator must beware lest knowledge of the tests 
become general on the part of new applicants. He will be 
prepared, if need be, to provide alternative forms to guard 
against coaching. 
He should be on the lookout for important changes in the 
job itself. 
He should keep a continual watch on the tests, and after 
making due allowances for their margin of reliability, check 
up the circumstances under which they make faulty pre- 
diction, and only then apply the proper remedies and 
changes. 
After the tests have been in operation for a considerable 
time, the investigator should find out what they have ac- 
complished in the way of increasing average production per 
man, decreasing breakage and loss, reducing labor turnover 
in the department, increasing the average level of applicants, 
and so forth, in comparison with other departments or plants 
where the improved methods of selection have not been 
introduced. These are secondary criteria of the worth 
of the tests. In obtaining them the statisticians and cost 
accountants will be able to help. Examples of the presen- 
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