Speakers
Description
Providing donors with information about the behaviour of others is a common strategy to nudge prosocial decision-making. The present study investigated the effect of ingroup vs outgroup information on participants' charity preferences using a Drift Diffusion Model approach.
In a joint evaluation scenario, we manipulated different levels of ingroup/outgroup preference ratios for two charities. Thirty-nine subjects were asked to choose one of the two charities that they favoured the most. We randomized three stimuli types (i.e., high, medium, and low ingroup ratio) in a total of 294 trials. We successfully demonstrated the ingroup effect through the modelling approach. Participants weighed ingroup information more and accumulated Evidence on ingroup behaviour faster and, therefore, decided more often and faster for the option that favoured the ingroup. The ingroup effect decreased for stimulus types with low ingroup ratio. However, some participants were not affected by the ingroup effect and consistently chose the most balanced ingroup/outgroup ratio. Future research should replicate the decision strategies, especially the strategy for the balanced ingroup/outgroup choice.
