Differential Item Functioning Reports in PARcore visualization studio include descriptive statistics reports and graphs related to differential item functioning analyses comparing reference and focal group(s). The available reports for a given request is combination of the options as select in the analysis template module and the scores selected in the test settings module. For more information, please see Analysis Templates - DIF & Test Settings - DIF
Reports available are:
Reference and Focal Criterion Score Frequency Distribution - This report includes univariate frequency distribution and summarized statistics for the criterion score for both a reference and focal group.
Reference and Focal Criterion Distributions Graphs - This report includes univariate distribution graphs for the reference group plotted alongside the focal group.
DIF Analysis Statistics and Standardized Percents - This report provides a table of the Item Level DIF statistics for each item being analyzed within a comparison, as well as a separate Standardized Percent table that displays the standardized percents for each item response.
DIF Item Response Curves - This report includes response-level graphs for every item being analyzed for both the reference group and the focal group.
C-Item Change Analysis - This report is produced when an analysis comparison had C flagged items before refinement was conducted. This report displays the before refinement and after refinement results side-by-side to allow for review and comparison for all impacted items.
Summary Across Comparisons - This report will summarize the DIF results for all items in an analysis, across all comparisons within that analysis.
DIF Counts by Category - This report will summarize the DIF Flag counts for all items in an analysis, across all comparisons within that analysis.
Table of Contents:
Reference and Focal Criterion Score Frequency Distributions
Reference and Focal Criterion Distribution Graphs
DIF Analysis Statistics and Standardized Percents
DIF Item Response Curves
C-Item Change Analysis
Summary Across Comparisons
DIF Counts by Category