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Hypothesized Mean Difference
Enter a mean difference with which to calculate the t test. If no value is en-
tered, a mean difference of zero is assumed.Labels
Indicate whether the fi rst row of the Y range and that of the X range include
header information.Alpha
Enter an alpha value used to calculate the critical values of the t shown in
the output.
See “Output Options” at the beginning of this section for information on
the output storage options.z-Test: Two Sample for Means
The z-Test: Two Sample for Means command calculates the unpaired two
sample z test. The test assumes that the variances in the two groups are
known (though not necessarily equal to each other). The output includes
both the one-tail and the two-tail critical values.