2.1.2. Participants
53 (29 female) randomly selected visitors of nexus were followed
by an unobtrusive observer. The visitors were not explicitly
told that they were being observed during their stay at the
museum. However, a sign at the entrance informed them that an
observational study was taking place in the exhibition. Visitors who
did not want to take part in the study could stick a button on their
clothes. This is a standard procedure used in observational studies