survey value list
I am making a survey for a conference. I want participants to rank their choices for each session. I don't want someone to choose the 1st choice more than once. I know its probably a validation, but can't figure out how to make it check the other fields. I don't use this that often but usually can figure things out.
It is probably on the forum but I don't know what to search for
diminishing value list--might work but not really sure how to do this.
unique value list?