Uploading psychometric targets to a LOFT test form

NOTE: Psychometric targets are not mandatory for generating LOFT tests. If you are using psychometric targets, you must tag items with the relevant IRT tag values. You can also include items without IRT tag values applied, for example in the case of pre-test items. For more information on IRT tag values, see (article).

You can upload psychometric targets in the Define Rules screen to set the desired Test Information Function (TIF) for all forms that will be generated by the LOFT algorithm.

This article explains how to upload psychometric targets to a LOFT section.

1. Navigate to the Define Rules screen

Select Define Rules in the Edit Test Form screen to create or edit the rules for the LOFT section.

2. Define content rules

NOTE: Psychometric targets are not mandatory, but you must define your content rules.

Each test generated conforms to all content and psychometric constraints, meaning that each test contains different but equivalent content. For more information on this functionality, read Defining rules for a LOFT section.

3. Import CSV file

To define psychometric targets, you must create a CSV file with two columns containing pairs of values:

Theta – the candidate’s ability level.
Information – the probability of the candidate giving the correct response.

NOTE: There is no limit to the number of values you can include. Adding more values increases the amount of time it takes to upload the data.

Select Import as CSV to browse your local files.

TIP: You can select Download sample CSV to download a spreadsheet containing example data.

Choose your file and select Open to import the data. A graph is plotted based on the values for θ (x-axis) and Information (y-axis). You can hover over the graph to view values at the plotted coordinates.

Select Download as CSV to download the data in a CSV file. Select Remove to delete the file.

4. Define the tolerance

NOTE: The Tolerance value defaults to 1, but this can be any value greater than 1.

You can define the Tolerance for generated tests. This gives some flexibility over the acceptable range that the TIF of each generated form must fall in to.

5. Generate your psychometric targets

NOTE: You must define your content rules before you can select Generate. For more information, read Defining rules for a LOFT section.

Select Generate to create your psychometric targets and navigate back to the Edit Test Form screen.