Correlated Averages. 



193 



Table II. 



Left Cubit 



Corresponding 



(above 18-05). 



Stature. 



19-3 



72-4 



18-7 



71-9 



18-8 



71-5 



18-4 



70 



18-6 



70-3 



19-6 



72-2 



18-4 



69 



18-3 



Q8 



19-3 



71-6 



18-2 



68-4 



18-1 



68-3 



18-7 



68-4 



*18 



70-2 



19-4 



71-1 



18-8 



68-3 



.5)280-6 



15)1051-6 



18-707 



70-107 



The mean deviation of the cubits, in absolute measure, is 



18-707-18-05 T , ,. , . ,. f ,, 



lne corresponding mean deviation or the 



•56 



statures is 



70-107-67-2 

 1-75 



; assuming from Mr. Galton's tables 



in Proc. Roy. Soc. 1888 that 18-05 and 67*2 inches are the 

 respective mean values of the cubit and stature, *56 and 1*75 

 their respective quartiles. For the coefficient of correlation 

 we have 



mean deviation of cubit in absolute measure -f- corresponding 

 mean deviation of stature 



= 1-17 -r 1-66 =-7 nearly. 



The truer value is '8, as determined by Mr. Galton from 

 some hundreds of observations ; but we must not expect an 

 accurate result from a few observations here instanced by 

 way of paradigm. 



In the work of this example I have purposely allowed one 

 mistake not largely affecting the result to stand by way 

 of warning ; the 18 marked with an asterisk in the second 

 table which, being below the mean value of the cubit, has no 



PhiL Mag. S. 5. Vol. 34. No. 207. Aug. 1892. O 



