STATISTICAL METHODS. 



Offspring. 



It was desired to determine the correlation between the eye-color 

 of the offspring and that of their great-grandparents Clearly the 

 ranges of the classes given above are not quantitatively equal nor 

 determinable Consequently a fourfold table was formed by dividing 

 the population into those having eyes whose color was gray blue-green, 

 or lighter, and those having dark gray, hazel, or darker eyes. This 

 gives a good basis for calculation If the dark gray and hazel eyes 

 had been grouped with the lighter eyes it would have made quadrant 

 a entirely too large; and there is nothing in the nature of the data 

 that strongly favors one division more than another 



1113 

 From the tables. 



Offspring 



.31 

 .30 



.01 



. 39886 

 .38532 



01354 



.15 

 .14 



01 



.18912 

 . 17637 



.01275 



h - .38532 + ( 1 354 X .002785) = .389091 

 A; -. 17637 4- (1. 275 X. 001060) = .177722 



