Multi-version assessments

Plom is designed for giving multi-version assessments suitable for crowded classrooms and multiple sittings.

You provide several versions of your assessment, and Plom interleaves questions from each version to create a large number distinct assessments.

Plom produces a different PDF file for each student by “slicing-and-dicing” your input “sources”.

Restrictions

For this interleaving to be possible, and for scoring to be practical, different versions of a question must take the occupy the same page(s) and must be worth the same number of points.

Loosening these restrictions is probably possible in theory, but none of the built-in tooling will help you do this.

Any questions that share a page must be the same version (this will happen automatically if you let Plom create the version mapping).

Controlling which questions are multiversioned

If you want a question to always come from version 1, specify select = [1] under that question while creating the specification. You can also use select = [1, 2] to specify that question will be chosen from versions 1 and 2. Omitted select is the same as specifying a list of all versions.

The question-version mapping

Tip

The first time you use Plom, we recommend using just a single version of your assessment (and skipping this section!)

When creating a multi-versioned assessment, a critically-important step is the creation of the “QV map” or the “question-version mapping”, which tells Plom what versions to expect for each question and for each paper.

You can have Plom create this mapping for you, where the assessment specification describes which versions each question may be drawn from.

Alternatively, finer control is possible by uploading a .csv file specifying which assessment version should be used for each question on each paper. In this case, the versions for each question in the assessment specification are overridden.

Caution

Its a good idea to download and backup a copy of your QV-map. If something goes catastrophically wrong, it (and the specification) are crucial components to recreate your assessment elsewhere.

Multiversioning FAQs

I want to use different versions of my ID page

For example, maybe you want to interleave versions 1 and 2 for section 101 and version 3 for section 102. In this case you might want to write “Section 101” on the front (ID) page of papers numbered 1-199 and “Section 102” on papers 200-350. This can be done by adding a id.version column to your custom “QV map” .csv file.

Danger

Versioned ID-pages is a new feature, without much (any?) real-world testing. Use at your own risk. If you’ve tested it, please get in touch so we can remove this message following your act of bravery.

Can I create my own per-student PDFs and use multiversioning?

Yes. You need only provide Plom with your chosen question-version map.