INDIVIDUALS AND MEASUREMENTS CONSIDERED. 



53 



In most cases the differences are apparently statistically significant 

 in comparison with their probable errors. Thus our series of infants, 

 both male and female, are certainly more highly correlated in their 

 weight and length than the series studied by others. 



Summarizing the results of this brief and superficial comparison, 

 it appears that while our series differ in correlation, they may never- 

 theless be considered to show a very satisfactory general agreement 

 in both mean, and variability with babies studied by others. Con- 

 sidering the possible influence of race, age, and social status, the 

 agreement seems rather remarkable. 



We assert, therefore, that we are dealing with the constants of 

 "normal" male and female infants, not merely because they are appar- 

 ently normal from the comparative standpoint of the obstetrician, but 

 because they give statistical constants in fair agreement with those 

 for babies studied by others. 



We now turn to the constants for adults. Since these are funda- 

 mental to the determination of many of the relationships in subsequent 

 sections, we shall give them for each of the various subseries. The 

 constants for stature appear in table 8, those for body-weight in 

 table 11. 



TABLE 8. Statistical constants for stature in adults of Nutrition Laboratory series. 



If the criterion of the suitability of our series of individuals were 

 mean stature only, we should be embarrassed by the wealth of available 

 materials for comparison. Stature is one of the more conspicuous and 

 more generally interesting characteristics of races or of the populations 

 of different geographic divisions. The number of average statures 

 available is therefore very large. But our comparison involves not 

 merely the average value, but the distribution of the statures around 

 the average. Hence we must base our comparisons on series which 

 have full data for the determination of variability as well as of type. 



