Structural-model Approach: Tractable Cases

In this paper, we continue our research on the algorithmic aspects of Halpern and Pearl’s causes and explanations in the structural-model approach. To this end, we present new characterizations of weak causes for certain classes of causal models, which show that under suitable restrictions deciding causes and explanations is tractable. To our knowledge, these are the first explicit tractability results for the structural-model approach. 1Institut für Informationssysteme, Technische Universität Wien, Favoritenstraße 9-11, 1040 Vienna, Austria. E-mail: [email protected]. 2Dipartimento di Informatica e Sistemistica, Università di Roma “La Sapienza”, Via Salaria 113, 00198 Rome, Italy. E-mail: [email protected]. Alternate address: Institut für Informationssysteme, Technische Universität Wien, Favoritenstraße 9-11, 1040 Vienna, Austria. E-mail: [email protected]. Acknowledgements: This work has been partially supported by the Austrian Science Fund Project Z29-INF and by a Marie Curie Individual Fellowship of the European Community (Disclaimer: The authors are solely responsible for information communicated and the European Commission is not responsible for any views or results expressed). Results of this paper appear in the Proceedings of the Eighteenth Conference on Uncertainty in Artificial Intelligence (UAI-2002), August 1-4, 2002, Edmonton, Alberta, Canada. Copyright c 2002 by the authors 2 INFSYS RR 1843-02-03