Title
A generalization of Nemhauser and Trotter's local optimization theorem
Abstract
The Nemhauser-Trotter local optimization theorem applies to the NP-hard Vertex Cover problem and has applications in approximation as well as parameterized algorithmics. We present a framework that generalizes Nemhauser and Trotter's result to vertex deletion and graph packing problems, introducing novel algorithmic strategies based on purely combinatorial arguments (not referring to linear programming as the Nemhauser-Trotter result originally did). We exhibit our framework using a generalization of Vertex Cover, called Bounded- Degree Deletion, that has promise to become an important tool in the analysis of gene and other biological networks. For some fixed d � 0, Bounded-Degree Deletion asks to delete as few vertices as possible from a graph in order to transform it into a graph with maximum vertex degree at most d. Vertex Cover is the special case of d = 0. Our generalization of the Nemhauser-Trotter theorem implies that Bounded-Degree Dele- tion has a problem kernel with a linear number of vertices for every constant d. We also outline an application of our extremal combinatorial approach to the problem of packing stars with a bounded number of leaves. Finally, charting the border between (param- eterized) tractability and intractability for Bounded-Degree Deletion, we provide a W(2)-hardness result for Bounded-Degree Deletion in case of unbounded d-values.
Year
DOI
Venue
2009
10.1016/j.jcss.2010.12.001
Journal of Computer and System Sciences
Keywords
DocType
Volume
maximum vertex degree,w[2]-completeness,k vertex,graph algorithms,bounded-degree vertex deletion,completeness result,vertex cover,nemhauser-trotter result,np-hard problems,deletion problem,np-hard vertex cover problem,polynomial-time data reduction,vertex problem kernel,nemhauser-trotter local optimization theorem,parameterized computational complexity,kernelization,biological network,np hard problem,combinatorial optimization,linear program,computational complexity,complete graph
Journal
77
Issue
ISSN
Citations 
6
26th International Symposium on Theoretical Aspects of Computer Science STACS 2009 (2009) 409-420
29
PageRank 
References 
Authors
1.08
35
4
Name
Order
Citations
PageRank
Michael R. Fellows14138319.37
Jiong Guo2149388.91
Hannes Moser336219.54
Rolf Niedermeier43465234.21