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Indiana University Studies 



whereby persons of very different abilities may be handled suc- 

 cessfully in the same group. Mr. Courtis in his practice pads 

 has devised one such method. In case such methods are used and 

 no limit is put upon the training the results of the tests might 



Fig. 23 VARIABILITY 



MIJLTIPLICATION 



show high variability. Even here, however, it might not be desir- 

 able because in the interests of all-round efficiency the training in 

 a particular skill should be limited. With this in mind it seems 

 that a low variability indicates wise selection of pupils, or . good 

 teaching, or both. 



