ANALYSIS OF THE WORKER oI 
ability is ended before he begins to make practical use of 
so-called general tests of mental alertness, output of energy, 
and the like. He will ordinarily find that the more specific 
he makes his own tests, the closer they will predict ability 
to do the work in question. But the varied samplings of 
ability made by the standard intelligence tests undoubtedly 
have their predictive value also. A worker who can do his 
tasks well is nevertheless apt to become discontented and 
restless if he is able to do work much more difficult and 
exacting than his job requires. Dissatisfaction and labor 
turnover traceable to such maladjustments are sometimes 
predictable from intelligence test data. Ability to learn 
certain kinds of occupational tasks is likewise significantly 
correlated with intelligence test score. For these reasons the 
investigator will not hesitate to include appropriate general 
tests in his program of examinations, even though he may 
be skeptical of the theory of the general common factor, 
regarding which controversies still rage. 
At the same time, no shrewd investigator will limit him- 
self to any single test for an assumed general ability. If he 
is interested in intelligence, he will use one test for intelli- 
gence in manipulating mechanisms, another for intelligence 
in dealing with people, a third for intelligence as applied to 
ideas, words, concepts, written symbols. Indeed he will 
choose his test according to the kind of mechanical con- 
trivances to be manipulated, the social level or type of 
situation in which social intelligence is to be demanded, or 
the particular realms of abstract ideas in which clear, quick, 
and accurate thinking is to be sought. He will go as far in 
the direction of measuring specific abilities as the nature of 
his problem permits. 
RELATIVE IMPORTANCE OF ABILITIES 
Before attempting to construct an examination for any 
particular item in his analysis of the abilities required, the 
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