EMPLOYMENT PSYCHOLOGY
Use should be made of simple graphs which bring out forcibly
 the most important facts. Distribution curves are
effective when vocational successes and failures are denoted
by distinctive symbols. Other graphs may be constructed to
show the percentages of successes selected and failures eliminated
 by the various methods of hiring. The investigator
by showing the value of mass results may minimize the impression
 made on the layman by the individual who stands
out as an exception to the rule and who by contrast to the
others assumes exaggerated importance.
RELATIVE ECONOMIC VALUE
If greater accuracy of prediction is possible by the use of
the examinations than by the customary methods of selection,
 the investigator must compute or estimate as accurately
as he can how much, in the course of a year, this saving
will be. Perhaps the predicted economies through improved
selection will not equal the cost of installing and administering
 the examinations. Sometimes, on the other hand, these
predicted economies are so large as to seem incredible at
first. In any event, the facts are essential. The research
worker should be impatient of mere hopes or vague opinions
regarding the relative cost and money value of selection
methods old and new.
Relative cost of administrating the old and the new methods
 is unimportant compared with the savings on the payroll
 effected through improved selection. Nevertheless, it is
usually advisable to estimate this cost by obtaining actual
figures on such savings as these:
Advertising. This is commonly advertising in the “Help
Wanted” columns of newspapers and magazines, and for
comparative purposes should be stated in terms of the cost
per successful employee obtained.
Correspondence. The cost of correspondence with applicants
 is another item of expense. This consists chiefly of the

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