832 MEMOIRS NATIONAL ACADEMY OF SCIENCES. [vol.xv, 



stage and likewise from the journeymen stage to the expert. Those inferior mentally would 

 stick at the lower levels of skill or be weeded out of the particular trade. On this hypothesis 

 one begins to question the accuracy of the personnel interviewing procedure. It is to be noted 

 that the hypothesis does not assume that skill and intelligence are synonymous. It merely 

 involves the assumption that other things being equal, the more intelligent will succeed better in 

 any given trade. The validity of this hypothesis will be brought out later in connection with 

 some data derived from occupational groups that have been trade tested. 



It is well to point out in passing that "other things" are not equal. In addition to intel- 

 ligence we have a special ability fitting one for a special trade and we have "trade customs" 

 that operate to promote from one level of expertness to a higher one on the basis of time spent 

 in the trade. This latter fact militates against a selection of only the most efficient in the higher 

 levels of skill. According to this custom the weak and the strong, the efficient and the inefficient, 

 alike proceed from the apprenticeship stage to the expert stage merely by fulfilling the require- 

 ment of time. The classification of soldiers into the A (apprentice), J (journeymen), and E 

 (expert) groups of skill in any trade and occupation by the personnel interviewing method was 

 based partly on the recognition and utilization of this concept that time spent in the trade is 

 the chief differentiating factor. In so far as the personnel system utilized such a criterion it is 

 to be inferred that mistakes were made. The data presented would indicate the desirability 

 of objective measurements of trade ability. 



While it is probable that mistakes were made as indicated above it is also probable that 

 many soldiers were classified in occupations in which they actually possessed no ability. The 

 use of trade tests in the camps indicates that approximately 30 per cent of the men claiming 

 trade ability are really novices in that trade. Thus the table of occupational intelligence 

 standards must be looked upon as far from perfect, as being merely indicative and as repre- 

 sentative in a general way only of conditions as they exist in depot brigades receiving draft 

 quotas selected under the provisions of the selective service act. Such limitations upon the 

 accuracy of the standards do not invalidate the use of such a table in preventing the misplacement 

 of the poorest 10 or 25 per cent of each occupational group. Such rough and practical use 

 would probably justify itself in a resulting increased percentage of successful placement. 



The above criticisms must not be emphasized to the exclusion of certain features of the 

 study that are of the utmost significance. This significance is not limited to its function as an 

 additional aid for Army personnel work but has wider application in the fields of economic 

 theory, employment management, and vocational guidance and training. 



Figure 57 brings out the fact that there seem to be four or five occupational levels. The 

 highest level might be termed the professional level, and is probably subdivided into two parts — 

 those professional groups having very high educational and professional standards (median 

 intelligence rating A) and those professional groups having slightly lower educational and 

 professional standards (median intelligence rating B). The next lower level contains such 

 occupational groups as clerical workers, technical workers, and probably those skilled mechanics 

 and skilled operatives who because of high average inteUigence and leadership become foremen 

 (the median intelligence of this level isC+). In the next lower level we have apparently 

 a larger number of occupational groups than in any other. The bulk of these occupational 

 groups fall under the heading of skilled mechanics and skilled operatives and the semiskilled 

 worker (median inteUigence of this level is C). The lowest level is next and contains those 

 occupational groups that may be characterized as unskilled labor (median intelligence of this 

 level is C — ). 



To demonstrate whether the differences between these four or five levels are significant, 

 statistical methods were utilized in the case of the midmost occupations in each group. In 

 the lowest occupational level teamsters are midway in intelligence between laborers and 

 barbers. The ratings for teamsters therefore were taken as representative of that occupa- 

 tional level. Similarly, locomotive firemen were taken as representative of the next higher 

 level, telegraphers as representative of the next higher level, accountants of the next higher 

 level, and engineering officers of the highest level. 



