DOCKERAY : PHYSICAL FATIGUE AND MENTAL EFFICIENCY. 213 



The average time of recall for each day is given in Table 

 IVa, but instead of giving the mean variation, the number 

 of responses that required more than 10,000 <? or less than 

 3000 a are given in Table IV6. The averages in this table 

 were obtained from the total number of individual responses, 

 while the final averages in Table IVa were obtained by taking 

 the average of each day's average. 



In case any one should wish to make a more careful study 

 of the results than these tables permit, a complete duplicate 

 copy of all the results used in compiling these tables may be 

 procured from the general library of the University of Michi- 

 gan or the University of Kansas. 



RESULTS. 



Table la. — Addition Tests. Average number of problems, and per cent 

 correct, from total daily records given in five-minute periods. (For 

 number of cases, see Table 16.) 



