17.9.2.1 The (PSS) Two-Sample T-Test Dialog Box

Supporting Information

Select check box to output results to the Results Log.

Power	Compute power for specified sample size.
Sample Size	Compute sample size for proposed power.

1st Group Mean	Mean of Group 1.
2nd Group Mean	Mean of Group 2.
Standard Deviation	Pooled standard deviation for the two samples.
Alpha	Probability of rejecting the null hypothesis when it is true.
Hypothetical Power(s)	Specify spaced-separated list of hypothetical power(s). Available when Calculate = Sample Size.
Hypothetical Sample Size(s)	Specify spaced separated list of hypothetical sample size(s). Available when Calculate = Power.
Alternative Hypothesis	Select a Alternative Hypothesis for two-sample t-test Not Equal Perform a 2-sided test for tail. Used to test 1st Group Mean is significantly different from 2nd Group Mean . Greater than Perform a right-tailed test. (When Calculate is set to Sample Size, 1st Group Mean should be greater than 2nd Group Mean for a Greater than Alternative Hypothesis.) Less than Perform a left-tailed test. (When Calculate is set to Sample Size, 1st Group Mean should be less than 2nd Group Mean for a Less than Alternative Hypothesis.)

Controls to be used when supplying additional power or sample size values by worksheet dataset:

When calculating power (Calculate = Power).

More Hypothetical Sample Size(s)	Select to activate the Hypothetical Sample Size(s) Column input controls.
Hypothetical Sample Size(s) Column	Specify column of sample size values. Available when More Hypothetical Sample Size(s)... is selected.

When calculating sample size (Calculate = Sample Size).

More Hypothetical Power(s)	Select to activate the Hypothetical Sample Size(s) Column input controls.
Hypothetical Power(s) Column	Specify column of power values. Available when More Hypothetical Power(s)... is selected.

Determine where to create the output report worksheet. For more information, see Analysis Report Sheets.