In this study, we consider an shikake, an embodied trigger for behavior change, to prevent umbrellas theft. We put a poster with a questionnare asking “Have you ever had a sad feeling from umbrella stolen?” on an umbrella stand to appeal to the feeling of guilty. People was able to vote for the questionnaire using build-in stickers. We conducted experiments at University campus for 111 days in total and revealed that the number of umbrella theft was reduced if the poster was set up. We concluded that a poster with a questionnaire seemed to be effective for umbrella theft prevention.
