Arguments for Qualitative Risk Assessment: The StAR Risk Adviser

Calculating risk is relatively straightforward when there is reliable statistical evidence on which to base a judgment. However, novel technologies are often characterised by a lack of such historical data, which creates a problem for risk assessment. In fact, numerical risk assessments can be positively misleading in such situations. We describe a decision support system – StAR – that gives quantitative assessments where appropriate, but which is also able to provide qualitative risk assessments based on arguments for and against the presence of risk. The user is presented with a summary statement of risk, together with the arguments that underlie this assessment. Furthermore, the user is able to search beyond these top-level arguments in order to discover more about the available evidence. Here we suggest that this approach is well-suited to the way in which people naturally make decisions, and we show how the StAR approach has been implemented in the domain of toxicological risk assessment.     

Applying Dialectic Agents to Argumentation in E-Commerce

Reaching an agreement or understanding through argumentation is an important aspect of decision making in a virtual society as well as in our real society. In this paper, we consider compromise (Aufheben) and concession (weaker Aufheben) as a simple form of Hegelian dialectical reasoning, which we think are desiderata to deliberate or cognitive agents. We then propose an argument-based agent system that allows for the issue modification among agents concerned during argumentation and reaching an agreement or understanding through argumentation with the dialectical reasoning capability. We illustrate its potential usefulness by showing applications to seller and buyer agents and traveling salesman agents in e-commerce.     

A LOGIC OF ARGUMENTATION FOR REASONING UNDER UNCERTAINTY

We present the syntax and proof theory of a logic of argumentation, LA. We also outline the development of a category theoretic semantics for LA. LA is the core of a proof theoretic model for reasoning under uncertainty. In this logic, propositions are labeled with a representation of the arguments which support their validity. Arguments may then be aggregated to collect more information about the potential validity of the propositions of interest. We make the notion of aggregation primitive to the logic, and then define strength mappings from sets of arguments to one of a number of possible dictionaries. This provides a uniform framework which incorporates a number of numerical and symbolic techniques for assigning subjective confidences to propositions on the basis of their supporting arguments. These aggregation techniques are also described with examples.     

一种基于辩论的决策方法研究

为了解决动态开放环境下决策方案可行性论证的难题,将辩论理论与实用推理结合提出了一种新的适用于多属性决策的辩论框架,定义了论据的类型和论据之间可能存在的攻击关系。将基于辩论的多属性决策过程分为用户需求获取、方案可行性论证和可行方案选优3个阶段,通过论据及其攻击关系对方案的可行性进行辩论论证。最后采用一个医疗决策问题对该框架的应用进行了示例说明,结果表明,该框架能够较好的处理信息不完整、不一致条件下的决策问题。     

高大模板工程方案的编制和专家论证及监理

结合具体工程实例,详细地介绍了高大模板工程方案的编制、专家论证及实施监理,得出了该工程在浇筑过程中未出现任何异常情况,高大支模的施工能够在安全和质量保证的前提下顺利完成的结论。     

基于JADE的多Agent辩论设计

该文基于JADE平台,立足辩论这一多Agent交互模式,从消息的封装、本体的表示、交互过程以及争议生成等方面设计了多Agent辩论的实现机制,实验表明这种设计是很有实用意义的。     

拓展溯因逻辑程序设计的辩论理论基础

讨论一类扩展的溯因程序,它包含经典否定、缺省否定、一致性约束以及溯因推理机制,论文的主要思想是：⑴本文限制某些假说（包括不相容假说）的攻击能力这样的出发点,定义一种更符合直观理解的“反驳”与“击败”概念,其中的Ⅱ－型击败关系具有动态的特点;⑵首次尝试一致性约束可以引起假说间的反驳与是一致笥约束不再仅仅是全局性的相容约束,基于这些思想提出的完全类语义拓展了Ｄｕｎｇ所奠定的溯因逻辑程序设计的辩论理论基     

分级论辩系统的逻辑研究

近年来,形式论证已逐渐成为人工智能领域的研究热点之一。自Dung于1995年提出抽象辩论框架起,学术界普遍认为论辩的核心任务是在各种基于外延的语义下对论点集进行评估,以确定其辩护状态。分级论辩系统(Graded Argumentation System,GAS)是对经典Dung型论辩系统(Dung-style Argumentation System,DAS)的推广,通过一般化DAS语义的两个核心性质,即无冲突性和可接受性,来提供更细化的论点状态概念。当前的论辩系统语义等效性研究主要集中在框架和论点层次上,可为其结构约简提供有力的保证。针对两个不同分级论辩系统中论点的语义等效问题,首先运用分级模态逻辑(Graded Modal Logic,GML)形式化分级论辩系统的片段,然后建立并证明了分级论辩系统基于外延的语义和GML公式之间的一一对应关系,最后定义分级互模拟关系并证明其蕴含分级论辩系统的4个重要的语义等价性。