192 



Prof. F. Y. Edgeworth on 



i. e. 18*75 nearly, and similarly 38 cubit-deviations measuring 

 on an average 19*25. But it is not necessary in general (the 

 prevalence of the law of error being presumed) for the pur- 

 pose of calculating the coefficient to work up the materials as 

 in Mr. Galton's Table II., or Table III. It suffices to take 

 the figures from the original observations pell-mell as they 

 come ; in fact it is better to proceed thus, as we avoid the 

 inaccuracy involved in assuming that all the observations in 

 each small compartment, e. g. between 18*5 inches and 19*0 

 inches, have the same measure — 18*75 inches. I take an 

 example from some of Mr. Galton's unmanipulated observa- 

 tions which he has kindly submitted to me. The raw material 

 consists of a table like the following, each column giving the 

 measurement of one organ, each row the measurements on 

 one man, — in the random order in which the visitors to the 

 Anthropometric laboratory presented themselves. Here is a 

 specimen : — 



Table I. 



Statures. 



Left Cubits. 



72*4 19*3 



71-9 18*7 



71*5 18*8 



70 18*4 



66 18 



70*3 18*6 



72-2 19*6 



69 18*4 



68 18-3 



64*4 18*2 



65*5 16*8 



66*1 17*1 



71*6 19*3 



68*4 18*2 



65 17*3 



63*7 16*8 



62*3 16*5 



(There are other columns with which we are not at present 

 concerned.) From the right column I pick out all the figures 

 which are above 18*05 (the mean value of the cubit) and 

 write them down in a new column, as thus ; — • 



