PLIABILITY AND ADEQUACY OF FARM-PRICE DATA 
39 
The farm price of veal calves is less variable than that of beef 
cattle in the Northern States, but is very highly variable in Ala- 
bama, where practically all farm prices except cotton are highly 
variable. Table 18 shows that the number of reports received from 
both New York and Wisconsin was sufficient to keep the probable 
error at a point where four times the relative probable error was 
less than 4 per cent. The farm price of veal calves is more reliable 
than the farm price of beef cattle, and it is nearly as dependable 
as that of hogs. 
HORSES AXD MILK COWS 
The farm prices of dairy cattle and of horses per head are more 
variable than the prices of beef cattle or veal calves per 100 pounds 
live weight. The price of hogs per head was much more variable 
than the price per 100 pounds live weight, The value per head 
includes not only the variability in value per pound due to finish, 
condition, quality, and age, but also the differences caused by size 
and weight, The variability in milk-cow prices, as shown in Table 
19, was about the same in Georgia, a southern State, as in New 
York and Wisconsin, two dairy States. The variability of the 
June, 1925, sample for Wisconsin, as reported by the regular price 
reporters, was about the same as the variability of the January 1, 
1926, sample as reported by the crop reporters, but the larger sample 
in January reduced probable error to a point where four times 
the relative probable error is less than 5 per cent for both milk 
cows and horses. In the larger States, where the sample is of fair 
size, the probable error is such that the four times the relative 
probable error is seldom above 10 per cent. 
Table 19. — Farm prices of horses and milk coivs: Selected illustrations of size 
of sample, measures of dispersion, and provable errors 
Class of livestock, State, and 
date 
Milk cows, per head: 
New York, November, 1925 
Wisconsin — 
June, 1925 
Jan. 1, 1926 2 
Georgia, November, 1925.. 
Maryland, March, 1926.. .. 
Horses, per head: 
Indiana- 
June, 1925 
Jan. 1, 1926 3 
Maryland, March, 1926 
Number 
of 
reports 
105 
68 
273 
52 
26 
74 
478 
25 
Average 
price 
(arith- 
metic 
mean) 
Dollars 
82.21 
66.74 
66.78 
34.62 
74.60 
82.62 
78.06 
101. 40 
Stand- 
ard devi- 
ations of 
reports 
Dollars 
20.35 
17.38 
17.23 
8.00 
24.95 
24. 50 
28.20 
31.90 
Coeffi- 
cient of 
varia- 
bility 
Per cent 
24.8 
26.0 
25.8 
23.1 
33.5 
29.7 
36.1 
31.5 
Probable 
error 
of the 
average 
price or 
mean 
Dollars 
1.38 
1.42 
.70 
.75 
3.31 
1.92 
.87 
4.30 
Relative 
probable 
error 
Per cent 
1.7 
2.1 
1.1 
2.2 
4.4 
2. S 
1.1 
4.2 
Four 
times 
relative 
probable 
error l 
Per cent 
8.4 
4.4 
8.8 
17.6 
9.2 
4.4 
16.8 
i The probabilities are ninety-nine out of one hundred that the average of a much larger sample collected 
in the same way and at the same time would not vary from this average by more than four times the 
probable error. 
2 Jan. 1 value of milk cows per head as reported by crop reporters, from about half the regular list, on 
Jan. 1, 1926. 
3 Jan. 1 value of horses over 2 years of age, per head, as reported by crop reporters. 
