The extensibility of the endowment effect to others is mediated by degree of intimacy

Recent studies have suggested that the endowment effect may actually be a type of self‐referent cognitive bias due to the mere ownership of an object. However, it is not adequately understood how the ownership of an object affects the endowment effect. The current research is the first to explore if the endowment effect could be extended to different ownerships. The results suggest that the endowment effect extends to goods owned by their mothers, romantic partners and close friends, but not acquaintances. Furthermore, the level of intimacy between individuals and mothers/romantic partners/close friends/acquaintances mediates the relationship between the effect of ownership and the extensibility of the endowment effect. These findings are consistent with the mere ownership effect that ownership increases valuation by enhancing the salience of the self.