The difference between Partners and Strangers designs in public goods experiments

Purpose – The purpose of this paper is to focus on conditional cooperation and investigate whether the difference in contributions between Partners and Strangers designs in linear public goods experiments can be explained by differences in beliefs. Design/methodology/approach – The author conducted linear public goods experiments by using Partners and Strangers designs with belief eliciting their group member’s contributions. Findings – The author shows that the difference in the magnitude of the responsiveness of contribution to belief (i.e. the marginal contribution to belief) creates different contribution levels in Partners and Strangers designs. Research limitations/implications – The presented results imply that having a strategic motive increases contributions by increasing the magnitude of the responsiveness of contribution to belief rather than by raising belief level. Originality/value – The main claim of this paper is that “marginal contribution to belief” rather than “belief level” causes the difference in contribution levels between Partners and Strangers. This is the first proven evidence of a difference in belief between Partners and Strangers.