CORRELATED VARIABILITY. 35 



X 2 ) = 1142-9 9+1652 ") 



= + 806* + 814 + 829 J- -*- n = ^ = 2.5625 

 - SnAfXi) 200 



= - 49 - 51 J 



- 5l5 , = - 4535 X .4605 = ^||f 



o- lC r 2 = 1.7195 X 1.7304 = 2.9754; p = -|4^ = - 79 1 9 



.0 1 04 



4/2000 X 1.627 



SPURIOUS CORRELATION IN INDICES. 



When two characters A and 5 are measured in each individual 

 of a series of individuals, and each absolute magnitude is trans- 

 formed into an index by dividing it by the magnitude of a 

 third character (?as found in the same individual, a spurious 

 correlation will be found to exist between the indices of 

 A . B 

 C and C 



Let ?'i = the coefficient of variation of A ; 

 D a = " " " " B; 



V 3 = " " " '< " C; 



Po = " " " spurious correlation. 



The precise method of using p in modifying any determina- 

 tion of p is uncertain. Pearson recommends using p p as 

 the true measure of "organic correlation" in the case of 

 indices. 



HEREDITY. 



Heredity is a certain degree of correlation between the 

 abmodality of parent and offspring. The statistical laws of 

 heredity deal not with relations between one descendant and 



