Multiple Choice - Restrict Maximum Selectable Options

With the current implementation of the multiple choice question a configuration using also negative points is required to avoid particpants from beeing scored with maximum points by simply selecting all available options. For getting rid of this need to use negative points the following feature is to be implemented.

1 Requirements

An optional restriction for the maximum amount of selectable options is required. This restriction has to affect while presenting the question in the test object as well as in the learning module. The question previews has to be considered too.

A new numeric setting "Maximum Selectable Options" as to be added to the configuration screen of the multiple choice question. Valid values for this field are the integers between 1 and the amount of available options. To keep the currently valid behaviour available this field can simply be left empty, no restriction will affect the participant when selecting answer options in this case. QTI Export and Import are to be completed with this new setting.

When a restriction of selectable options is active a corresponding hint is shown to the participant while answering the question (e.g. "Select 2 of 4 Answer Options"). The selection of more than the allowed amount of options is avoided by using javascript. When the maximum amount of options is selected, all other checkboxes get disabled. When one of the selected options gets deselected, the disabled checkboxes get enabled again. Because of this mechanism can be bypassed easily there is also a need for a serverside validation of the amount of selected answer options. In case of an invalid answer, the answer is not stored and the question is shown to the participant again involving a corresponding failure message. The submitted and invalid selection is reset in full.

Within the correction mode the new setting won't be adjustable, since in-or decreasing this value does not make sense in any kind.

Existing questions will not be migrated in any kind, the new setting will just be left empty, so the cuurently known behaviour won't be changed for this questions.

Note: The disabled checkboxes in the screenshot above was pimped with a opacity of 0.5, we should think about a global adjust of disabled elements in general, because some browsers in some OS present enabled/disabled form elements very similar.

2 Additional Information

• Idea / concept: Universität Göttingen
• Interest in funding: Universität Göttingen
• Maintainer: Björn Heyser, bheyser@databay.de
• Implementation of the feature is done by Databay AG AG
• Testcases by: (please add your name if you want to create the testcases for this feature)

3 Discussion

Jackisch, Ingo [jackisch]: My co-worker Irina Waltschläger had the same proposal a couple of days ago. To further specify the suggestion, so this seems to be a common need.

Loewe, Anja [aloewe] 11.04.2016: We are also very interested in this functionality in exactly the way described.

JourFixe, ILIAS [jourfixe], July 25, 2016: We highly appreciate this suggestion and schedule it for 5.2.

4 Implementation

The number of selectable answers in a Multiple Choice-Question is determined by the input field "Answering Limitation". Please note the minimal value is "1". When entering a value greater than the actual number of possible selections, users receive an error message upon form validation. If the number of mandatory selections is supposed to be unlimited, the field is to be left empty.

From the learners perspective, when the feature is activated, the number of selectboxes is checked by JavaScript. Once the maximum number of selections is made, the remaining checkboxes are deactivated, "greyed out". In order to select a different checkbox, another one must be deselected first.

Test Cases

Test cases completed at 26. Aug 2016 by Heyser, Björn [bheyser]

• C51: Multiple-Choice-Frage erstellen
• C7233: Multiple Choice Frage erstmalig beantworten
• C7329: Multiple Choice Frage erstmalig beantworten

Approval

Approved at 2016-08-23 by .