An Argumentative Approach for Explaining Preemption in Soft-Constraint Based Norms

TL;DR

DSA-framework can provide explanations why one consequence is obligatory or forbidden by soft-constraint based norms represented as logical constraint hierarchies and it is formally proved that, under local optimality, DSA-framework can provide explanations why one consequence is obligatory or forbidden.

Abstract

Although various aspects of soft-constraint based norms have been explored, it is still challenging to understand preemption. Preemption is a situation where higher-level norms override lower-level norms when new information emerges. To address this, we propose a derivation state argumentation framework (DSA-framework). DSA-framework incorporates derivation states to explain how preemption arises based on evolving situational knowledge. Based on DSA-framework, we present an argumentative approach for explaining preemption. We formally prove that, under local optimality, DSA-framework can provide explanations why one consequence is obligatory or forbidden by soft-constraint based norms represented as logical constraint hierarchies.

Figures (5)

• Figure 1: DSA-framework from Example \ref{['ex:overtaking']}
• Figure 2: Explanation for why $r$ is forbidden in Example \ref{['ex:overtaking']} with the situation $\Pi = \{p,q\}$
• Figure 3: Explanation for why $r$ is obligatory in Example \ref{['ex:overtaking']} with the situation $\Pi = \{q\}$
• Figure 4: DSA-framework from Example \ref{['ex:2']}
• Figure 5: Explanations from Example \ref{['ex:2']}

Theorems & Definitions (22)

• Definition 1: obligation
• Example 1: overtaking
• Definition 2: derivation state
• Definition 3: derivation state space
• Definition 4: DS-argument
• Definition 5: DSA-framework
• Proposition 1
• proof
• Definition 6: local optimality
• Proposition 2