Question
In: Statistics and Probability
Two random samples are taken, one from among UVA students and the other from among UNC...
Two random samples are taken, one from among UVA students and the other from among UNC students. Both groups are asked if academics are their top priority. A summary of the sample sizes and proportions of each group answering yes'' are given below: UVA (Pop. 1):UNC (Pop. 2):n1=81,n2=85,p^1=0.8 p^2=0.663
Find a 96.3% confidence interval for the difference p1−p2 of the population proportions.
Solutions
Expert Solution
Solution :
Given that,
n1 = 81
1
= 0.8
n2 = 85
2
= 0.663
Point estimate of difference between two proportions
=
1 -
2
= 0.8 - 0.663
=
Our aim is to construct 96.3% confidence interval.
c = 0.963
= 1- c = 1- 0.963 = 0.037
/2
= 0.0185
= 2.086 ..(use z table)
Margin of error =
*
= 2.086 * 
= 0.1692
Required interval is
Point estimate
Margin of error
0.137 0.1692
(0.137 - 0.1692 , 0.137 + 0.1692 )
(-0.0322 , 0.3062)
Required 96.3% interval is (-0.0322 , 0.3062)
orchestra answered 2 years agoRelated Solutions
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