Unformatted text preview: n Sample Stdev 1 15 52 4.61 2 15 57 4.83 Test the alternative hypothesis that the mean lives
G. Baker, Department of Statistics
G.
are different.
University of South Carolina; Slide 10 How do we know if we can assume
How
equal variances?
equal
Confidence Interval on σ21/σ22
Hypothesis Test
Hypothesis
H0: σ21/σ22 = 1
Ha: σ21/σ22 = 1 G. Baker, Department of Statistics
G.
University of South Carolina; Slide 11 Test for Equal Variances
Confidence Interval Approach:
Confidence
– If CI does not contain 1 we have
If
sufficient evidence to conclude that the
variances are different. We can not
assume equal variances.
assume
– If the CI contains 1, we will continue to
If
assume that the variances are equal.
assume G. Baker, Department of Statistics
G.
University of South Carolina; Slide 12 Test for Equal Variances
Hypothesis Test Approach:
H0: σ21/σ22 = 1
Ha: σ21/σ22 = 1
If we reject H0, there is sufficient evidence to
conclude that the variances are different. We
can not assume equal variances.
If we fail to reject H0, we will continu...
View
Full
Document
This note was uploaded on 01/12/2014 for the course STA 509 taught by Professor Wang during the Fall '13 term at South Carolina.
 Fall '13
 Wang
 Statistics

Click to edit the document details