Joint Conversation Specification and Compliance

Abstract

Formal specifications of protocol-oriented agent interactions have focused mainly on the semantics of the constituent agent communication language (ACL). In existing work, the semantics of a conversation policy is derived from the semantics of its individual communicative actions (CA) and there is no notion of persistency and compliance to the whole conversation policy. We argue that a proper theoretical treatment of conversations cannot be simply derived compositionally from the semantics of individual CAs. Accordingly, we develop a theory of joint conversations that is independent of its constituent CAs. We treat the process of a group following an interaction protocol as a persistent joint communicative action (JCA) by the group. This paper specifies the $\mathcal L_{JCA}$ logic based on Cohen and Levesque 1990 joint intention (JI) theory [2] and develops a framework in $\mathcal L_{JCA}$ logic for representing and reasoning about joint conversations. We define compliance in a joint conversation and we prove salient properties of joint conversations. Amongst others, we prove the existence of a Nash equilibrium in a bilateral interaction, and that our framework ensures an agent’s compliance to the rules of the interaction in the sense that each participant jointly intends to uphold the whole conversation and to adhere to the conversation policy.