IRT TBLT - Reports and Table of Contents

• Parameter Statistics -  This report includes various different reports related to the parameter statistics from TBLT.  Included reports are:
  • Quasi Newton Report:  Displays the results of the quasi-newton minimization
  • Parameter Comparison:  Displays the new (transformed) and reference a-parameter, b-parameter, and (b-d)-parameter values for each of the common items.    
  • ICC Comparison:   Displays the weighted and unweighted comparison statistics for each of the common items.

• Comparison Plots -  This report includes up to five different common item plots, depending upon the analysis options selected.  Possible plots are:
  • b-parameter Untransformed:  Plots the untransformed new b-parameter and reference b-parameter values for all common items.
  • b-parameter Transformed:  Plots the transformed new b-parameter and reference b-parameter values for all common items.
  • a-parameter Transformed:  Plots the transformed new a-parameter and reference a-parameter values for all common items.
  • (b-d)-parameter Transformed:  Plots the transformed new b-d parameter and reference b-d parameter values for all common items.  This report is only applicable to analyses that include polytomous items.
  • Common Item Test Characteristic Curves:  Plots the common item test characteristic curves for new, reference, and transformed. This is an optional report and will not always be produced. 

• Summary Statistics and Correlations -  This report includes the a-parameter and b-parameter summary statistics (such as N, Mean, etc.) for the new and reference common items used in the TBLT analyses. The statistics are summarized separately by dichotomous items and/or polytomous items.   For polytomous items additional summaries of the (b-d)-parameters are also calculated and displayed.  

• TBLT Problem Items  This report includes two different reports related to the possible problem items from TBLT analyses.  Included reports are:
  • Problem Item Report:  A summary report for each flag value indicating how many items in the analysis were flagged.
  • Problem Item Profile Report:  This table contains only the items that were flagged in the analysis, which flag each item triggered, and the a-parameter and b-parameter statistics for the item.

• Parameter and Ability Distributions  - This report includes frequency distributions and summary statistics for the a-parameter, b-parameter, and ability distributions from TBLT.   Additional distributions by Form, LIC, and AU are available if the option was selected in the request details.