846 MEMOIRS NATIONAL ACADEMY OF SCIENCES. ivol.xv. 



In the previous study of branches of the service made on the basis of the examining in 

 the four original camps (Part II, loc. cit.) a comparison was made of six branches (infantry, 

 machine gun, artillery, engineer, sanitary train, field signal battalion) on the basis of median 

 scores and of percentage of A and B grades. The present study shows an increase over the 

 former figures in the percentage of A and B grades in these branches of from 2.9 per cent in 

 the engineers to 8 per cent in the case of the machine-gun battalions. The field signal bat- 

 talions, however, show a decrease of 3 per cent. The general tendency toward an increase 

 may perhaps be due to a lower norm in alpha than in examination a. The exceptional increase 

 in the case of the machine-gun battalion may be due to the fact that in later times it was 

 recognized that a considerably higher quality of man was needed for this special duty. It 

 is noteworthy that the present comparison gives the same rank order among these six branches 

 as was found in the previous study except for the single inversion of infantry and machine- 

 gun battalion where the 8 per cent increase of the latter is responsible. The only other striking 

 difference that now occurs is the increase by 10.1 per cent over the older findings with regard 

 to percentage of A and B grades in the supply train. We have no information which would 

 tend to explain this difference. 



A large part of the divisions trained in the spring of 1918 at Camps Sheridan and Cody 

 were examined after assignment from the depot brigade. At Camp Kearny at a later time 

 men were assigned to organizations on the basis of a "table of psychological needs." This 

 table was based upon a combination of the percentages of the various psychological grades 

 obtained by the 10 best, 10 average, and 10 poorest men as selected in numerous organizations 

 by their commanding officers. The rank order of the six branches is precisely the same in 

 our present results as in the "table of psychological needs" at Camp Kearny. The actual 

 percentages of A and B grades are somewhat higher at Camp Kearny. At Camp Sheridan 

 the percentage of A and B men in the sanitary train was comparatively quite low, while at 

 Cody the percentage of A and B men in machine-gun battalions was comparatively very high; 

 otherwise there was close agreement, and the order of the branches was very similar to the 

 one at which we have here arrived. 



The intelligence ratings of officers of different branches of the service at the four original 

 camps were discussed in Part II, pages 494 ff. Significant differences in median scores and 

 in percentages of A and B grades were found to exist between different branches of the service. 

 The combined rank order from highest to lowest obtained through this treatment of results 

 from all four camps combined was : Engineers, Field Artillery, Infantry, Quartermaster Corps, 

 Medical Corps, Dental Corps, Veterinary Corps. 



The principal Hollerith sample for officers by branch of service is exhibited in tables 392 

 to 396. Table 397 was derived therefrom to show again the percentages of the different grades 

 in various branches. Figure 59 presents the chief results of table 397 in graphic form. Cal- 

 culation on the basis of the percentage of A and B grades gives exactly the same rank order 

 in the seven branches mentioned. The percentages of A and B grades were approximately 

 7 to 18 per cent less with examination a than with alpha. This is probably due chiefly to the 

 more rigorous and exacting norms used in the former examination. The additional branches 

 of the service now considered are also of interest where any considerable number of cases is 

 given. 



