I don't want survey participants to have to register for tokens and cookies can easily be deleted -- is there a way to prevent multiple responses per participant by IP (or by something else other than tokens/cookies)?
No, because several machines on the same network (like in a school) may have the same IP
In my case I'll miss out on more participants by making them register for tokens than I will by limiting responses to one per network. Thanks for confirming, I'll try to implement it myself.
