提出判断上下文依赖论证框架是否可被价值排序替代的方法。
From Contexts to Values: Context-Dependent Defeat in Abstract Argumentation
- 用上下文决定攻击是否成立，而非固定价值排序。
- 发现多数上下文依赖框架无法用单一价值排序模拟。
- 提供算法与工具，适合逻辑与人工智能研究者使用。
在基于价值的论证中，观众对价值的排序决定了哪些攻击能构成击败。但在许多场景中，决定因素并非观众，而是情境：同一攻击在不同程序阶段或监管条件下可能成功或失败。我们提出的上下文依赖论证框架（CDAF）直接建模这一现象：一组论点、一个攻击关系，以及根据上下文切换攻击有效性的击败函数，使每个上下文对应一个普通的杜恩框架。这引出一个核心问题：上下文是否为本质新特征，还是可用带每上下文排序的价值赋值来重现击败函数，从而将CDAF归约为价值论证框架（VAF）？本文给出了该问题的多项式时间判定算法，并对相关难题给出上界（从NP到Σ^p_3）。同时提供了经验证的参考实现与测量：可表示性罕见，且随上下文数量增加迅速下降。
原文摘要 · Abstract (English)
In value-based argumentation, an audience's ordering of values decides which attacks succeed as defeats. In many settings the deciding factor is not the audience but the circumstances: the same attack may succeed at one procedural stage, or under one regulation, and fail at another. Context-dependent argumentation frameworks (CDAFs), a model we recently introduced, capture this directly: one set of arguments, one attack relation, and a defeat function that switches each attack on or off per context, so every context induces an ordinary Dung framework. This raises a reduction question: is context genuinely new, or can one value assignment with per-context orderings reproduce the defeat function, collapsing the CDAF into a VAF? We present a polynomial-time decision procedure for this question and map the harder neighbouring problems, with upper bounds from NP to $Σ^p_3$. We also present a validated reference implementation and a measurement: representability is rare and falls fast with the number of contexts.
Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品；中文卡片由大模型生成，请以原文为准。