In: Statistics and Probability
An Egg producer wants to estimate the mean number of eggs produced per chicken. A sample of 16 chickens shows they produced an average of 21 eggs per month with a standard deviation of 1.7 eggs per month.
a. Develop a 99% confidence interval for the population mean
b. What is the best estimate of the population mean?
c. What distribution would you use for this analysis?
solution
Given that,
= 21
s =1.7
n = 16
Degrees of freedom = df = n - 1 = 16- 1 =15
At 99% confidence level the t is ,
= 1 - 99% = 1 - 0.99 = 0.01
/ 2 = 0.01 / 2 = 0.005
t /2 df = t0.005,15 = 2.947 ( using student t table)
Margin of error = E = t/2,df * (s /n)
= 2.947 * ( 1.7/ 16) =1.2525
The 99% confidence interval estimate of the population mean is,
- E < < + E
21 - 1.2525 < < 21+ 1.2525
19.7475 < < 22.2525
( 19.7475,22.2525 )
point estimate= = 21