The Steiner tree problem on graphs: Inapproximability results

Miroslav Chlebík, Janka Chlebíková
2008 Theoretical Computer Science  
The Steiner tree problem on weighted graphs seeks a minimum weight subtree containing a given subset of the vertices (terminals). We show that it is NP-hard to approximate the Steiner tree problem within a factor 96/95. Our inapproximability results are stated in a parametric way, and explicit hardness factors would be improved automatically by providing gadgets and/or expanders with better parameters.
doi:10.1016/j.tcs.2008.06.046 fatcat:hw3lm5eg7nf5xgmw6wupbp7wnm