T-Test for Dependent Samples

Select the Advanced tab of the

dialog box to access options to determine the detail and formatting of the t-test for the dependent samples results spreadsheet as well as the p-value for highlighting.

Summary: T-tests

Click this button to compute the t-tests for dependent samples and display the results in a spreadsheet.

The detail and formatting of the results depend on the selections on this tab.

Box & whisker plots

Click this button to produce a cascade of box and whisker plots for the variables.

First, the Box-Whisker Type dialog box that contains options for the box and whisker type displays, with ne box plot for each variable in the first list vs. each variable in the second list.

Box and whisker plots summarize the distribution of the dependent variable for each group.

Specifically, each group is represented by one box and whisker component, which is made up of three parts:

A central line to indicate central tendency or location
A box to indicate variability around this central tendency
Whiskers around the box to indicate the range of the variable

Display

The options in this group box determine the detail and formatting of the t-test for dependent samples results spreadsheet that is produced when you click the Summary button.

Matrix of t-tests

When this option button is selected, click the Summary button to produce the following three summary results spreadsheets reporting for each pair of variables (from the two lists):

The significance level (p-valuezc) for the respective t-value
The mean difference
The t-values for the respective difference

Detailed results

When this option button is selected, click the Summary button to produce one summary results spreadsheet reporting for each t-test:

Means
Standard deviations
Valid N
Others

Display long variable names

Select this check box to display the long variable names (see Variable Specs Editor), along with the short names in the first column of the result spreadsheets.

If no long variable names have been specified for any of the selected variables, the setting of this check box has no effect.

p-value for highlighting

The default p-value for highlighting is .05.

You can adjust this p-value by entering a new value in the edit box or using the microscrolls.

For more details on p-value, see Elementary Concepts.

CI for estimates

Select this check box to compute confidence interval estimates for the differences between means.

You can request confidence limits for any p-value using the corresponding field. By default, the 95% confidence limits (p=.05) is computed.

For more information on confidence limits, see Descriptive Statistics - "True" Mean and Confidence Interval.

T-Test for Dependent Samples - Advanced tab