From the PARcore Data Visualization Studio Landing Page, navigate to this report by selecting the DIF Frequency Distributions report icon.   This report is only applicable for requests that include the Analysis Type of Item Analysis - Differential Item Functioning. 

The bento box menu icon at the top left of the report can be used to navigate back to the Landing Page.
 




When first launching the report it will be empty.  Make initial filter selections in order to visualize the report.  Any filter with a red asterisk indicates it is required to have a selection made before the report can be displayed.


Filters
Refer to Visualize Results for general information about filter navigation for any report.  The filters for this report are:



 

• Analysis - select one analysis sequence number to view at a time.  The analysis sequence number will reflect the sequencing from Request Details for this request.
  • Upon first initializing this dashboard, the filter will display as (Choose your analysis) and a selection must be made. 
  • Select the search icon (magnifying glass) and enter search text to see Analysis filter options for the request you are viewing.  Using an asterisk in the search text box will display all possible analyses to choose from.  
  • Once the current analysis results have been reviewed, continue to use the search feature or utilize the slider arrows (< and >) to view each analysis one at a time.  If you only have one analysis to view, the slider arrows will be disabled.
  • The filter description will include the criterion score being analyzed as well as the reference and focal group.  Only one reference/focal group comparison will be displayed at a time.

• Refinement Type - select one refinement to view at a time.  
  • Upon first initializing this dashboard, the filter will display as (Choose refinement type.) and a selection must be made before any data is visualized.  Use the dropdown filter to display the possible refinements stored for this comparison group.  
  • The available refinement type(s) to choose from depend upon the user selected options for this analysis as well as the analysis results.  The available options are:
    • No Refinement:  This will appear if the user selected "No" to the analysis template option to Refine Criterion Score.  This will be the only refinement option available.
    • None Required:  This will appear if the user selected "Yes" to the analysis template option to Refine Criterion Score but the comparison analysis resulted in no C items and therefore no refinement was performed.  This will be the only refinement option available.
    • Before Refinement:  This will be available if the user selected "Yes" to the analysis template option to Refine Criterion Score and the comparison analysis resulted in at least one C item.  The dropdown menu should show both "Before Refinement" and "After Refinement" as options.  Selecting Before Refinement will display the frequency distributions and summary statistics before refinement was performed. 
    • After Refinement:  This will be available if the user selected "Yes" to the analysis template option to Refine Criterion Score and the comparison analysis resulted in at least one C item.  The dropdown menu should show both "Before Refinement" and "After Refinement" as options.  Selecting After Refinement will display the frequency distributions and summary statistics after criterion refinement was performed.

• The Statistics to Display filter has a set of default statistics pre-selected for display.  If needed, change the filter selections to modify which statistics are displayed in this section of the report.  Only statistics stored for the analysis being viewed are available in the filter menu.  
  • If changing the default filter selection values, any selection changes will persist when changing the Analysis filter being viewed.  If the filter was changed to display statistics that are not relevant to the next analysis a blank report may be produced with a message to adjust your filters. 

• An ellipsis will display at the end of any statistic value that is truncated due to length.  A tooltip appears when hovering over a statistic value to display the full rounded statistic value without truncation.

Frequency Distributions section
The frequency distributions for the reference group and focal group for the selected analysis will appear in a table on the right of the report.

• The Distribution Columns to Display filter has a set of default statistics pre-selected for display.  If needed, change the filter selections to modify which statistics are displayed in this section of the report.  Only statistics stored for the analysis being viewed are available in the filter menu.  
  • If changing the default filter selection values, any selection changes will persist when changing the Analysis filter being viewed.