Texas Instruments TI-NSPIRE Software Manual page 245

This test is useful in determining if the difference between a sample
mean and a population mean is statistically significant when you know
the true deviation for a population.
t-test (tTest)
(one-sample
t-Test
population mean, m, when the population standard deviation, s, is
unknown. It tests the null hypothesis H
alternatives below.
: mƒm
• H (m
:
a 0
: m<m
• H (m
:<
a 0
: m>m
• H (m
:>
a 0
This test is similar to a z-test, but is used when the population is small and
normally distributed. This test is used more frequently than is the z-test
because small sample populations are more frequently encountered in
statistics than are large populations.
This test is useful in determining if two normally distributed populations
have equal means, or when you need to determine if a sample mean
differs from a population mean significantly and the population
standard deviation is unknown.
2-SampZTest (zTest_2Samp)
(two-sample
2-SampZTest
populations (m
1
population standard deviations (s
: m
hypothesis H
0
: m ƒm
• H (m
a 1 2
: m
• H <m (m
a 1 2
: m
• H >m (m
a 1 2
2-SamptTest (tTest_2Samp)
(two-sample
2-SamptTest
populations (m
1
population standard deviation (s
: m
H =m is tested against one of the alternatives below.
0 1 2
: m ƒm
• H (m
a 1 2
: m
• H <m (m
a 1 2
: m
• H >m (m
a 1 2
Using Lists & Spreadsheet
t
test) performs a hypothesis test for a single unknown
ƒm
)
0
m
)
0
m
)
0
z
test
and m
) based on independent samples when both
2
=m is tested against one of the alternatives below.
1 2
ƒm
)
1: 2
m
)
1:< 2
m
)
1:> 2
t
test) tests the equality of the means of two
and m
) based on independent samples when neither
2
ƒm
)
1: 2
m
)
1:< 2
m
)
1:> 2
: m=m
against one of the
0 0
tests the equality of the means of two
)
and s
) are known. The null
1 2
or s
) is known. The null hypothesis
1 2
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