KR 2008 Tutorials

Tutorial 1 (Monday 13:30-15:00)

Michael Thielscher: KR Techniques for General Game Playing


A General Game Player is a program that accepts formal descriptions of arbitrary games and plays these games without human intervention. One of the grand challenges for Artificial Intelligence, General Game Playing requires to combine techniques from a wide range of areas including knowledge representation, automated reasoning, heuristic search, planning, and learning. This tutorial will focus on the challenges for Knowledge Representation and Reasoning raised by General Game Playing:
  • Formalizing game rules
  • Mapping game descriptions to efficient representations
  • Extracting knowledge from game descritions
  • Proving properties of games

  • Tutorial 2 (Monday 15:30-17:00)

    Tony Hunter: Argumentation Systems


    Argumentation systems are being developed with the aim of reflecting how human argumentation uses conflicting information to construct and analyse arguments. Argumentation involves identifying arguments and counterarguments relevant to an issue (e.g. What are the pros and cons for the safety of mobile phones for children?). Argumentation may also involve weighing, comparing, or evaluating arguments (e.g. What sense can we make of the arguments concerning mobile phones for children?) and it may involve drawing conclusions (e.g. A parent answering the question "Are mobile phones safe for my children?"). In addition, argumentation may involve convincing an audience (e.g. A politician making the case that mobile phones should be banned for children because the risk of radiation damage is too great). Formalizations of argumentation have been extensively studied, and some basic principles have been established. In Abstract argumentation, originally proposed in the seminal work by Dung, arguments are treated as atomic, and a graph-based formalization is used where each node is an argument, and each arc denotes one argument attacking another argument. In contrast, logic-based formalizations assume a set of formulae and then exhaustively lay out arguments and counterarguments, where a counterargument either rebuts (i.e. negates the claim of the argument) or undercuts (i.e. negates the support of the argument). In the logic-based approach, an argument is normally defined as a pair (X,p) where X is a minimal consistent subset of the knowledgebase that entails p. A variety of underlying logics have been considered for the entailment and consistency conditions including classical logic, defeasible logics, and description logics. Both the graph-based and logic-based approaches provide principled ways of determining which arguments are warranted (i.e. undefeated). Recent topics of research in argumentation systems include the development of algorithms and implementations, the formalization of rhetorical aspects of argumentation, and the formalization of argument-based dialogue systems. In this tutorial, we will consider both graph-based and logic-based formalizations of argumentation, introducing some of the basic concepts, and reviewing a range of proposals and results.