THE MEASURE OF COMPARATIVE PRODUCTIVENESS 3I9 
of the basis for selection and retention makes it possible 
to simplify these perplexities. In the instances given it 
appeared, when these men were recommended for dis 
charge, that there was a lack of correlation between 
selection and retention in the case of A. However, a 
comparison between the two sets of records showed that 
this lack of correlation existed only at one point, and by 
investigating this point, the matter was rectified and the 
correlation maintained at a higher level. 
Evidently, therefore, this method of finding the corre 
lation between selection and retention has a double as 
pect. First, the strictly statistical, by which the degree 
of correlation may be numerically expressed. Second, the 
corrective, which reveals the exact points of difference 
between selection and retention and thereby makes it 
possible to apply the correct remedies. 
There are, to be sure, many factors in the selection and 
retention of employees which have not been considered 
here, such as length of service, religious or political views, 
family status, etc. These, however, are ethical questions 
and must be settled on ethical rather than on scientific 
grounds. Psychology can offer only certain general 
principles to aid in their solution. However, as long as 
the chief object of an industry is to serve or to produce, all 
of these questions must be treated in the light of their 
effect upon the employees’ productiveness. The industry 
or organization which does not attain a certain standard of 
productiveness or service can not survive; but the attain 
ments of any organization depend upon the comparative 
productiveness of its units, the individuals who compose 
it. Comparative productiveness, therefore, is the “lead ”, 
the criterion, with reference to which all the factors of 
selection and retention must be determined.