Although much is known about cooperation, the internal decision rules that regulate motivations to initiate and maintain cooperative relationships have not been thoroughly explored. Here, we focus on how acts of benefit delivery and perceptions of social value inform gratitude, an emotion that promotes cooperation. We evaluated alternate information-processing models to determine which inputs and internal representations best account for the intensity with which people report experiencing gratitude. Across two experiments (Ns = 257 and 208), we tested 10 models that consider multiple variables: the magnitude of benefits conferred on beneficiaries, the magnitude of costs incurred by benefactors, beneficiaries' perception of how much benefactors value their welfare, and beneficiaries' value for the welfare of their benefactors. Across both studies, only beneficiaries' change in social valuation for their benefactors consistently predicted gratitude. Results point to the need for further research and contribute to the growing literature linking cooperation, social emotions, and social valuation.
Keywords: cooperation; gratitude; information processing; open data; open materials; preregistered; social emotions; welfare trade-offs.