Matrix - crashing when rows contain a dot (.)


Last question at Pavlovia Survey

I’ve noticed a behaviour in the matrix type of question that can lead to a crash at the end of the survey.
If I have many items to add to the rows of the matrix, I simply use the Rows setting in the question settings. If there is a dot in my items I paste, and this item is selected when the survey is taken then it crashes.

Now it is my understanding that these are saved as key-value pairs and that the key cannot contain dot. But the same behaviour does not happen when I use the radiogroup type of question. So I am a bit confused as to the source of this error. Perhaps someone can shed some light on this?


Error message

I think that the issue is this.

A radiogroup is one question with multiple answers, so {question} can be used to access the answer selected.

A matrix contains multiple questions (one for each row), and a . is used to access the answers, .e.g {question.row1}

If you have a . in the row value, the survey will not be able to distinguish between, say {question . row.1} and {question.row . 1}

Thanks @wakecarter for the explanation.

Then I think it is important to stress that for the setting that allows us to enter multiple options at once we must:

  • Either respect the convention i.e. Row 1 | your option here
  • or your option here sanitised | your option here

I think I will be using the latter both for columns and rows as I want my data to show the real values selected rather than having something like the below and then trying to figure out what was selected

As always many thanks for your support



I would recommend:

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