Towards A Formal Model of Opportunism Based on Situation Calculus

In social interactions, it is common for one party to possess more or better knowledge about a specific transaction than others. In this situation, parties who are more knowledgeable might perform opportunistic behavior to others, which is against others’ interest thus leading to relationship deterioration. In this study, we propose a formal model of opportunism based on situation calculus. Specifically, knowledge asymmetry and intention are modeled by adapting the standard possible-world model semantics, and value opposition is specified through defining a value evaluation function on situation based on the perspective of agents. We illustrate how to use our formal model through a simple example. By this model, we show that the judgment of opportunism is subjective since it depends on from which perspective agents evaluate the situation over their value, and it is not the intention, but the knowledge, of opportunistic agents to cause harm to others. Further study on its emergence and constraint mechanism can be carried out based on the formal model.