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Hello, I am making a survey for an election. For one ballot, I want to make it so that each voter can either select up to two people, or leave the question blank (for a blank ballot), or write in the "other" section to void it (spoilt ballot). I already set 2 to be the maximum number of selections (multiple choice question), but could I also make it so that if a voter clicks "other" they cannot select anything else? That would make the counting much easier, because it would make it impossible for someone to select one candidate AND ALSO the "other" option. In this last case the entire ballot should be considered as spoiled, but the only way for me to find these kinds of spoiled ballots would be to look at each ballot individually and I would love to not do that, and just look at the aggregated answers. Thanks

Make the "other" option the "exclusive" option. 

 

OR:

or write in the "other" section to void it (spoilt ballot)

What do you expect the participant to write?
In my opinion it should be sufficient to add a subquestion labelled "VOID" (or whatever) and set this as "exclusive" option.
 

Joffm

Thank you so much, I hadn't seen that there literally was a voice to set up an "exclusive" answer. It worked perfectly.

Now I have another question though. The exclusivity solved perfectly the issue of identifying void ballots, but I now realize blank ballots are also a problem. I mean, right now with this system they're not detectable through the final statistics that show the aggregated answers, and again I'd have to look at the ballots one by one to find the blank ballots.
Also, the question cannot be seen by everyone. I set some conditions for an elector to be able to see this specific question. So I also need to distinguish between a blank ballot and a ballot that couldn't vote for this specific question (right now the latter is shown in the statstics via the "not completed/not visualized" voice). Do you have any tips on how to do that?

Thanks again

You allow it to be empty.

can either select up to two people, or leave the question blank (for a blank ballot)

Of course this is not the best way, but your decision.

But anyway, you see if it is "empty" or "skipped" in the database. Either there is the condition to skip this question or not.
And in the so called "statistic" you may filter on this question.

Another option could be to add a hidden answer option "blank".
Then use an equation to set this option, if the question was left blank, but the condition was to show the question.

Joffm