By default, when you use the exception testing in Displayr (using arrows and/or font colors), individual columns will be compared to the average of the "other" dates in the table. However, some users may want to compare a date to the date preceding it. This article describes how to go from a table showing default significance differences (comparing to the complement of the cell - known as exception testing):
To a state where significant differences are shown against the previous time period in each row:
Requirements
- Familiarity with Displayr's significance testing settings. See: How to Apply Significance Testing in Displayr
- A document containing a table that has a Date/Time variable in the columns (i.e., the variable is not categorical but has a Structure set to Date/Time). If you need to convert your variable to a Date/Time variable, there are various methods outlined here: How to Create Date Variables in Displayr. If you want to test against the previous column and your data can't be converted into a typical Date/Time variable, please see a workaround in How to Test Against the Previous Period without a Date/Time Variable.
Method
1. Select the table which contains time periods in the columns.
2. From the Object Inspector, select Appearance > Significance > Advanced.
3. Select the Significance levels tab.
4. In the Show significance drop-down box, select Arrows, Font colors, or Arrows and Font colors.
5. Select the Test Type tab.
6. From the Date drop-down box, select Compare to previous period.
7. Select Apply to Selection to apply it to just the selected table or Set as Default to make it the default for all crosstabs with date variables in the document. To learn more about defaults, see: How to Set the Default Type of Significance Test.
The results are as follows:
Restore to Document Default Settings
To revert to the document's current default settings, click the Restore button:
Note: The Restore button will only be enabled when settings for the selected item(s) are different from the document's current default settings (settings saved by Set as Default). The Restore button will be disabled if you did not save any settings for the selected item(s). See: How to Set the Default Type of Significance Test to learn more about changing the default settings.
See also
Independent Sample Tests - Comparing Two Proportions and Independent Sample Tests - Comparing Two Means for a discussion of how Displayr computes tests on such tables.
Next
How to Apply Significance Testing in Displayr
How to Set the Default Type of Significance Test
How to Compare Significant Differences Between Columns
How to Change the Confidence Level at which Significant Differences are Displayed
How to Apply Multiple Comparison Correction to Significance Tests