Identity signaling and sustainable cooperation

The thesis studied identity signals' role in perceived trustworthiness and sustainable cooperation. Trust is central to cooperation but uncertain, so how people choose whom to trust and how trustworthiness perceptions change over time matters. The research found identity signals can convey trustworthiness and may sustain trust and cooperation via three mechanisms. First, behavioural and identity signals interact and differ in weight: men are generally seen as less trustworthy than women, but a man showing past prosocial behaviour, such as a charity donor badge, may partly offset that negative gender signal. Second, outgroup members can signal trustworthiness by adopting ingroup norms if the adoption is costly, like learning the ingroup language. Third, behavioural and identity signals differ in their impact on restoring trust after a breach.