16 American Statistical Association. 



REMARKS ON THE THEORY OF ANTHROPOM- 

 ETRY. 



By Feanz Boas, Ph.D. 



The theory of anthropometric statistics is based largely 

 upon Qnetelet's investigations, who endeavored to prove 

 that the distribution of anthropometric data follows the law 

 of chance. Some attempts to develop the theory further 

 have been made by Stieda and Ihering and by Francis Gal- 

 ton. The former emphasized the introduction of the aver- 

 age variation of measurements into the consideration of the 

 subject, the latter developed what has become known as the 

 method of percentile grades. Stieda was also the first to 

 express a doubt as to the general applicability of the law of 

 chance. 



The anthropometric charactei'istics of a group of people 

 are treated in various ways. Some authors consider the 

 average of the measurements the most valuable result ; oth- 

 ers prefer to compute the mean value, which is, more prop- 

 erly speaking, the probable value, as it is computed as that 

 value above and below which fifty per cent of the whole 

 series are found : still others compute the most frequent 

 value. Tlie followers of Francis Galton compute the mean 

 value and the points representing various percentile grades, 

 i. (?., points below which ten per cent, twenty per cent, 

 thirty per cent, and so forth, of the total series are found. 

 Anthropologists who study the physical characteristics of 

 races use mostly the method of seriation. They give the 

 percentage of cases of the series which fall between certain 

 limits. Still another method which is frequently applied 

 consists in the comparison of those percentages of the series 

 which lie above or below a certain limit. 



We will examine the merits of these methods. Whenever 



