How to explain the participation effect: is it a question of different expectations and communication? A preliminary investigation

This experiment is a preliminary test to explain the participation effect observed in Bortolami and Mittone (2009). The aim of this new version is to test whether the contributory gap is more properly justifiable in terms of pure environmental choices, or, on the contrary, whether the gap is more strictly related to behavioural dynamics. To verify the former hypothesis, an environmental change regarding communication is introduced. To test the latter, empirical and normative expectations are explicitly considered.