Unformatted text preview: at 27.G.. Baker,ofDepartment of Statistics
University South Carolina; Slide 7 Interpret the 95% confidence
Interpret
interval on µ1  µ2 of
(1.46, 8.54).
(1.46,
We have sufficient evidence to
We
conclude that there is a difference
between the means.
between
B. We have insufficient evidence to
We
conclude that there is a difference
between the means.
between A.
A. G. Baker, Department of Statistics
G.
University of South Carolina; Slide 8 Difference Between Means: µ1 – µ2
Difference
Format for Test Statistic:
Format Pt Est  Test Value
Standard Error
Test Statistic:
Test Z= ( y1 − y2 ) − (µ1 − µ 2 )0
σ 12
n1 + 2
σ2 n2 t df = ( y1 − y2 ) − (µ1 − µ 2 )0
2
1 2
2 s
s
+
n1 n2
G. Baker, Department of Statistics
G.
University of South Carolina; Slide 9 Two Samples from Independent Populations
An independent consumer group tested radial
tires from two major brands to determine
whether there was any difference in the
average tread life (thousands of miles). The
summary data is below:
summary
Brand n Sample mea...
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Full Document
 Fall '13
 Wang
 Statistics, Statistical hypothesis testing, G. Baker

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