Toward A Formalism for Conversation Protocols Using Joint Intention Theory

Abstract

Conversation protocols are used to achieve certain goals or to bring about certain states in the world. Therefore, one may identify the landmarks or the states that must be brought about during the goal-directed execution of a protocol. Accordingly, the landmarks, characterized by propositions that are true in the state represented by that landmark, are the most important aspect of a protocol. Families of conversation protocols can be expressed formally as partially ordered landmarks after the landmarks necessary to achieve a goal have been identified. Concrete protocols represented as joint action expressions can, then, be derived from the partially ordered landmarks and executed directly by joint intention interpreters. This approach of applying Joint Intention theory to protocols also supports flexibility in the actions used to get to landmarks, shortcutting protocol execution, automatic exception handling, and correctness criterion for protocols and protocol compositions.

OperettA: Organization-Oriented Development Environment

“…Interaction objectives can be more or less restrictive, giving the agent enacting the role more or less freedom to decide how to achieve the role objectives and interpret its norms. Following the ideas of [17], [14], we call such expressions landmarks, defined as conjunctions of logical expressions that are true in a state. Landmarks combined with a partial ordering to indicate the order in which the landmarks are to be achieved are called a landmark pattern.…”

Executing Specifications of Social Reasoning Agents

“…Kumar et al [12] describe the Request Conversation Protocol (RCP) for establishing a joint persistent goal (JPG). The difference between a Joint Intention (JI) and a JPG is in the mutual belief throughout executing the action that it is done as a team.…”

“…The formal definitions can be found in [12], but the description of a PWAG is useful here. "PWAG(X,Y,A,Q)" says agent X has a persistent goal to achieve A, given relevancy condition Q, and will have a persistent goal to notify Y that A is achieved, or becomes impossible or irrelevant (¬Q holds).…”

Embedding Landmarks and Scenes in a Computational Model of Institutions

“…The relative sophistication of a landmark specification can be affected by the logic that is used to define the condition, but in many respects this is a technicality. For example [18] use first order logic augmented with modal operators for propositional attitudes and event sequences, [12] use dynamic propositional logic with modal operators from the previous work, while [9] (p.126) has atoms, implying the conjunction of positive values, within a Kripke model and [1] uses linear-time temporal logic. More important is the actual purpose of landmarks, as [12] states:…”

“…A more detailed discussion follows in [12], where they are presented as propositions that are true in the state represented by the landmark (sic). The value of landmarks, and more specifically, their partial ordering into landmark patterns, is how they permit the identification of phases in a conversation protocol corresponding to the achievement of goals (and subgoals).…”