Nov. 19, 1917 
Study of Steers During Fattening Period 
385 
METHOD OF TAKING MEASUREMENTS 
All measurements taken are indicated in Table I. The initial and 
final weights were averages of individual weights taken on three con¬ 
secutive days at the beginning and close of the experiments. All body 
measurements except circumferences were made with the steel calipers 
shown in Plate 39, A. To the vertical standard, which was graduated 
in inches, were attached two movable horizontal crossbars. All circum¬ 
ferences were measured with a steel tape graduated in inches (PL 39, B). 
The steers were tied and placed on a level wooden floor while being 
measured. Owing to their restlessness, some of the measurements were 
difficult to obtain, especially those of the head. The measurement of 
length of neck was discontinued after the second year because of the 
impossibility of getting correct position and dimensions. The distance 
from hock to ground was another measurement which possessed a large 
experimental error. The probability of error in measurements is a 
factor not considered, thus necessitating a larger number of measurements 
to reduce the probable error. 
METHOD OF CALCULATION 1 
The method of calculation in the tables presented were as follows: 2 
SD x f 
The mean was obtained by the following formulae: A=—^--+H. 
/y (T) l ) 2 f TZDH ) 2 
The standard deviation was calculated as follows: (7 = A—1—- 1±_ 
n n 
The coefficient of correlation coefficient was worked by the formulae: 
liDxDyj 
naxvy 
The coefficient of variation was obtained as follows: C = - X100 per cent. 
a 
The probable error in each was determined as follows: 
Probable error of mean: E A = ±0.6745-^=; 
-yjn 
Probable error of standard deviation: E<j= ±0.6745 
V2 n 
Probable error of coefficient of correlation: £r= ±0.6745 
(1 -r 2 ) , 
* 
Probable error of coefficient of variation: E c = ±0.6745-7=. 
■\2n 
1 Davenport, C. B. statistical methods, with special reference to biological variation. 
ed. 3, p. 12-18, 44-45. New York and London, 1914- 
2 KEY TO FORMULA} : 
A =Means; 
o’— Standard deviation; 
r = Coefficient of correlation; 
C= Coefficient of variation; 
«« Population; 
S* Summation; 
H= Assumed mean; 
x= Character classified in vertical columns; 
Character classified in horizontal row; 
D ^Deviation from assumed mean. 
/“Frequency. 
