For every full submission to the survey in order to offer a token of appreciation of your invested time I will also donate 10 EUR to charity. The chosen charity is Deworm the World and it is recommended by the Effective Altruism Foundation (https://ea-foundation.org/ -> Donations -> Supported Projects).
This originally entailed 7.50 EUR for the participation in the Personality Survey and 2.50 for each round of the Relationship survey, but given feedback I abandoned the 2nd relationship survey. Now simply the Personality Survey is open, and every response will get the full 10 EUR for answering it, which should take between 35 and 45 min.
This I will cap this at 5000 EUR for now, as my funds are not unlimited and this project is entirely self funded.