no. 3.] PSYCHOLOGICAL EXAMINING IN THE UNITED STATES ARMY. 627 



cases to the number of two or three. At the lower end of a scale this phenomenon is probably 

 largely due to purely accidentally correct responses. The types of responses called for in the 

 alpha and beta tests, viz, simple lines, crosses, etc., makes accidental scores of from 1 to 3 or 4 

 points in some tests quite possible for individuals whose ability may be much lower than the 



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 2 



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face value of such scores would indicate. In the case of limitation at the upper end of the scale 

 massing of cases in the class interval next below the terminal one is accounted for by the fact 

 that particular items in a test may present more than usual difficulty to some individuals. If 

 a sufficient number of items of increasing difficultness are available, all individuals will automati- 

 cally find their levels by adjusting the test to themselves. This adjustment is possible because 



