42 
BULLETIN 1480, U. S. DEPARTMENT OE AGRICULTURE 
Table 22. — Farm prices of eggs and chickens: Selected illustrations of 
of sample, measures of dispersion, and prooaole errors 
Product, State, and date 
Number 
of reports 
Average 
price 
(arith- 
metic 
mean) 
Standard 
deviation 
of reports 
Coeffi- 
cient of 
varia- 
bility 
Probable 
error of 
the aver- 
age price 
or mean 
Relative 
probable 
error 
Four 
times 
relative 
probable 
error i 
Eggs (per dozen) : 
New York- 
July, 1925 
December, 1925 
Kansas- 
July, 1925 
December, 1925 
Nebraska — 
May,1925 
July, 1925 
December, 1925 
Missouri — 
July, 1925 
December, 1925 
Mississippi — 
July, 1925 
December, 1925 
Montana — 
July, 1925 
December, 1925. 
Connecticut — 
July, 1925 
December, 1925 
Georgia— November, 1925... 
Maryland— March, 1926 
Chickens (per pound) : 
Georgia— November, 1925... 
Maryland— March, 1926 
167 
201 
153 
164 
118 
147 
198 
79 
4S 
Cents 
35.6 
61.0 
24.2 
39.1 
22.8 
24.6 
39.0 
25.2 
41.4 
22.7 
45.7 
27.8 
50.8 
44.1 
71.1 
43.2 
27.1 
Cents 
4.7 
7.9 
1.9 
4 5 
1.5 
2.1 
5.2 
1.8 
4.9 
3.4 
6.3 
4.4 
6.6 
Per cent 
13.1 
13.0 
7.9 
11.5 
6.7 
8.5 
13.3 
7.1 
11.8 
15.1 
13.7 
15.8 
13.1 
Cents 
0.24 
.38 
.11 
.24 
.09 
.12 
.25 
.13 
.38 
.32 
.54 
.43 
.61 
Per cent 
0.7 
24 
17.9 
13.5 
40 
1.4 
1.2 
1.5 
1.2 
1.5 
1.4 
1.1 
1.3 
1.5 
1.5 
Per cent 
2.8 
2.4 
2.0 
2.4 
1.6 
2.0 
2.4 
2.0 
3.6 
5.6 
4.8 
6.0 
4.8 
6.0 
5.6 
4.4 
5.2 
6.0 
6.0 
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 prob- 
able error. 
The variability of egg prices is as low as 6 to 8 per cent in the Corn 
Belt during the months of heavy summer production, but it is nearly 
double that in these same States in December. In New York and 
Connecticut, where the production of winter eggs is relatively more 
important than in the Central States, the variability is about the 
same in July as in December. It is possible that the premium 
on high-quality near-by eggs in the East, especially near the larger 
cities, tends to increase the variability of the sample. The variations 
in the Mississippi and Georgia samples are much lower relatively 
than the variation in the price samples of most other Southern prod- 
ucts. Wide local differences existing in Western States such as 
Montana cause a wide dispersion in the egg prices received. 
Because of the relatively low variability of egg prices and the 
large number of reports received the probable error is not usually 
very large, and four times the relative probable error in many States 
is less than 2 per cent ; and even in such small States as Connecticut 
and Maryland four times the relative probable error does not exceed 
6 per cent. The farm price of eggs lends itself to this method of 
collecting price data. 
The two samples of chicken prices analyzed in Table 22 show about 
the same conditions as do egg prices, except that in the spring when 
" young fries " are bringing a premium, the range in price per pound 
is extremely wide and the variability of the sample is greater at that 
season of the year than at other times. 
