Question
In: Statistics and Probability
Independent random sampling from two normally distributed populations gives the results below. Construct a 95 %...
Independent random sampling from two normally distributed populations gives the results below. Construct a 95 % confidence interval estimate of the difference between the means of the two populations. η1 ¬= 82 (X_1 ) ̅ = 115 σ1 = 20 η2 = 83 (X_2 ) ̅ = 100 σ2 = 15
Solutions
Expert Solution
95% confidence interval for 
1 - 2 is
(
1 -
2) - Z *
sqrt [ 
1 / n2
+ 2 / n2
] < 1 - 2 <
(1 -
2) + Z *
sqrt [ 1 / n2
+ 2 / n2
]
(115-100) - 1.96 * sqrt [ 202 / 82 + 152 /
83) < 1 - 2 < (115-100)
+ 1.96 * sqrt [ 202 / 82 + 152 / 83)
9.601 < 1 - 2 <
20.399
95% CI is ( 9.601 , 20.399 )
orchestra answered 2 years agoRelated Solutions
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