Picture map of Europe with pins indicating European capital cities

Open Access research with a European policy impact...

The Strathprints institutional repository is a digital archive of University of Strathclyde's Open Access research outputs. Strathprints provides access to thousands of Open Access research papers by Strathclyde researchers, including by researchers from the European Policies Research Centre (EPRC).

EPRC is a leading institute in Europe for comparative research on public policy, with a particular focus on regional development policies. Spanning 30 European countries, EPRC research programmes have a strong emphasis on applied research and knowledge exchange, including the provision of policy advice to EU institutions and national and sub-national government authorities throughout Europe.

Explore research outputs by the European Policies Research Centre...

A new empirical study of weak backdoors

Gregory, P. and Fox, M. and Long, D. (2008) A new empirical study of weak backdoors. In: 14th International Conference on Principles and Practice of Constraint Programming, 2008-09-01.

Full text not available in this repository. Request a copy from the Strathclyde author

Abstract

Work by Kilby, Slaney, Thiebaux and Walsh [1] showed that the backdoors and backbones of unstructured Random 3SAT instances are largely disjoint. In this work we extend this study to the consideration of backdoors in SAT encodings of structured problems. We show that the results of Kilby et al. also apply to structured problems. Further, we analyse the frequency with which individual variables appear in backdoors for specific problem instances. In all problem classes there are variables with particularly high frequencies of backdoor membership. Backbone variables that do appear in backdoors typically appear in very few.