228 • 



MENTAL HYGIENE 



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O 



14- 



24- 



2OX 



2S% 



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d6-K' 9% 



4.5% 





Intelli^nce of these/ meru 

 as oUetermmSLWtheOljohatest 



The scientific measurement of intelligence, most frequently used 

 as individual tests, is a series of performance tests arranged in the 



order of difficulty. The 

 first of such tests was 

 worked out bv two French 

 psychologists, Alfred 

 Binet and Theodore 

 Simon. These tests have 

 been revised bv different 

 persons in America, and 

 among these revisions is 

 one by Terman, known 

 -ru A Ai u . . . .^««««n ■ '"^"^ TJie Stem ford Revision 



The Army Alpha test was given to 1,700,000 men m '' 



the United States army in the World War. It con- gf fJig Binet-SimOJl Scole. 

 sisted of 212 questions. Grade A was given to those 



answering correctly 135 or more of the 212 questions; This SCalc iucludcs tCStS of 

 grade B for 105 to 134 correct answers. A was earned 



by only 4.5S of the men. Compare the results attained memory, language COm- 

 by the other groups of men as shown in the table. -. . . n ■, 



prehension, size or vocab- 

 ulary, knowledge of familiar things, judgment, and many other 

 mental tasks that are a part of every child's experience. Stand- 

 ards, to show what children of certain ages should know, have been 

 established by comparisons of the results or ratings made by chil- 

 dren of definite ages in all sections of the country. For instance, 

 there are a certain number of questions that a six-year-old child is 

 supposed to answer correctly. If a particular child of six answers 

 less than this score, he is said to have a mental age, M.A., of four 

 or five, or Avhatever age that score is supposed to measure. If he 

 answers more than the required number, he may have a mental 

 age of seven, eight, or even more. Thus there are tests ranging 

 in difficulty from those for a three-^^ear-old child to those given 

 to an adult. For the practical purpose of measuring progress in 

 school the inteUigence quotient, I.Q., is used. This is obtained by 

 dividing a child's mental age by his age in years. This quotient 

 will usuallv remain fairlv constant from \'ear to vear, for his men- 



