Belief change in rational agents

在人工智能中的知识表示（KR）中，代理处理的问题域可以是特定的问题域（如诊断）、物理域（如机器人遇到的问题）或“虚拟”域（如网络提供的问题域）。在所有这些情况下，代理的知识通常是不完整的，在某种程度上是不准确的，并且是不断变化的。KR中的一个重要问题是管理这种信息的变化，无论代理是被告知一个新的事实，还是已经执行了一些操作，或者已经从不同的来源获得了一组观察结果。本研究的主要焦点是信念变化，即agent如何根据新的信息修改其信念。虽然已经开展了许多工作，但仍有一些关键问题尚未得到充分解决。例如，目前尚不清楚我们所拥有的正式模型是否能完全表征信念变化的各个方面；同样，对于智能体应该如何整合关于固定环境的一系列观察结果，也没有达成一致。这项研究将解决信念变化的问题，以及在一个可以执行行动的动态代理世界中更广泛的推理问题。首先，将开发描述信念变化方面的数学模型，其次，与此相辅相成的是，将在不同领域的适用性背景下开发和研究计算模型。一个次要的，但与之密切相关的研究主题涉及偏好推理。通常情况下，一个代理不仅有（严格的）目标要实现，而且还有一些理想的，但不是必须的，要建立的东西。还将讨论在规划中使用偏好，以及偏好在信念变化中的作用。

In Knowledge Representation (KR) in Artificial Intelligence, an agent deals with a problem domain which could be a specific problem area (such as diagnosis), a physical domain (such as encountered by a robot) or a "virtual" domain (such as provided by the web). In all such cases, the agent's knowledge will generally be incomplete, inaccurate to some extent, and constantly changing. An important problem in KR is to manage this change of information, whether the agent has been told a new fact, or has carried out some actions, or has been given a set of observations from different sources.The main focus of this research is on belief change, which deals with how an agent should modify its beliefs on the basis of new information. While much work has been carried out, there are crucial issues that have yet to be fully addressed. For example, it is not clear that the formal models that we have fully characterize all aspects of belief change; as well, there is no agreement as to how an agent should incorporate a sequence of observations about a fixed environment. This research will address the problem of belief change, and the wider problem of reasoning in a dynamic world of agents that can carry out actions. First, mathemetical models characterizing aspects of belief change will be developed, and second, complementary to this, computational models will be developed and studied in the context of their applicability in different areas.A secondary, but strongly related, topic of research concerns reasoning with preferences. Typically an agent will have not just (strict) goals to attain, but also things that are desirable, but not necessary, to establish. The use of preferences in planning, as well as the role of preferences in belief change, will also be addressed.