Transcript Chapter 8 Minitab Recipe Cards

Chapter 8
Minitab Recipe Cards
Confidence intervals for the
population mean
• Choose Basic
Statistics from the
Stat menu and 1Sample t from the
sub-menu.
• In the command
window select
Summarized data.
• For Example 8.6
enter 40 as the
Sample size, 3.47 as
the Mean, and 0.82
as the Standard
deviation.
• The confidence
interval appears in the
session window.
Hypothesis tests for differences
between population means
• Select Basic
Statistics from the
Stat menu then 2Sample t from the
sub-menu.
• Click Summarized data.
• Type in the Sample size,
Mean and Standard
deviation of the ‘own
brand’ sample in Example
8.19 (14, 34.9 and 1.4
respectively) in the First
row and the equivalent
figures for the premium
sample (17, 33.4 and 1.1)
in the Second.
• For the pooled estimate
of the standard error tick
Assume equal
variances.
• Click Options and
check that 0 is in the
space beside Test
difference.
• Change the
Alternative to
greater than.
• Click OK.
• The output in the
session window
includes the test
statistic, T-value and
the probability that the
test statistic occurs if
the null hypothesis is
true, P-value.
Paired t tests
• Enter the two sets of
data in Example 8.20
into C1 and C2.
• Choose Basic
Statistics from the
Stat menu then
Paired t from the submenu.
• Check that Samples
in columns is
selected.
• Type C2 for the First
sample and C1 for
the Second sample.
• Click Options and
specify the null
hypothesis value of
the mean of the
differences, 8, beside
Test mean and
change the
Alternative: to less
than.
• The output in the
session window
includes the test
statistic, T-value and
the probability that the
test statistic occurs if
the null hypothesis is
true, P-value.