Stevan Tomic

Stevan Tomic, Federico Pecora, Alessandro Saffiotti

Future robots should follow human social norms in order to be useful and accepted in human society. In this paper, we leverage already existing social knowledge in human societies by capturing it in our framework through the notion of social norms. We show how norms can be used to guide a reinforcement learning agent towards achieving normative behavior and apply the same set of norms over different domains. Thus, we are able to: (1) provide a way to intuitively encode social knowledge (through norms); (2) guide learning towards normative behaviors (through an automatic norm reward system); and (3) achieve a transfer of learning by abstracting policies; Finally, (4) the method is not dependent on a particular RL algorithm. We show how our approach can be seen as a means to achieve abstract representation and learn procedural knowledge based on the declarative semantics of norms and discuss possible implications of this in some areas of cognitive science.

Stevan Tomic, Federico Pecora, Alessandro Saffiotti

Interactions within human societies are usually regulated by social norms. If robots are to be accepted into human society, it is essential that they are aware of and capable of reasoning about social norms. In this paper, we focus on how to represent social norms in societies with humans and robots, and how artificial agents such as robots can reason about social norms in order to plan appropriate behavior. We use the notion of institution as a way to formally define and encapsulate norms, and we provide a formal framework for institutions. Our framework borrows ideas from the field of multi-agent systems to define abstract normative models, and ideas from the field of robotics to define physical executions as state-space trajectories. By bridging the two in a common model, our framework allows us to use the same abstract institution across physical domains and agent types. We then make our framework computational via a reduction to CSP and show experiments where this reduction is used for norm verification, planning, and plan execution in a domain including a mixture of humans and robots.