IV] 



STATISTICAL STUDY 



37 



the mode is identical with the mean. Stature in 

 inches may be taken as an example. A large number 

 of fathers and a son of each are measured to the 

 nearest inch ; it can then be found what is the 

 average measurement of sons for fathers of each 



-S^e 



rtf 



10 TO 



<l)[l63 



I" 367 

 l|- 



\ 



S 



\ 



\ 



;B 



60 61 62 63 64 65 66 67 68 69 7O 71 72 73 74 75 76 77 



Statures of Fathers 

 Fig. 6. Diagram of correlation between fathers and sons. 



height from the lowest value to the highest. It will 

 be found that the mean deviation of the sons from 

 the mean of the population is less than the deviation 

 of the fathers for each class of fathers. The average 

 ratio between the mean deviations of the sons to the 



