Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.13/922189
- Title
- W-Hierarchies defined by symmetric gates
- Author/Creator
-
Fellows, Michael;
Flum, Jörg;
Hermelin, Danny;
Müller, Moritz;
Rosamond, Frances
- Institution
- The University of Newcastle. Research Division, Office of the Deputy Vice-Chancellor (Research)
- Description
- The classes of the W-hierarchy are the most important classes of intractable problems in parameterized complexity. These classes were originally defined via the weighted satisfiability problem for Boolean circuits. Here, besides the Boolean connectives we consider connectives such as majority, not-all-equal, and unique. For example, a gate labelled by the majority connective outputs true if more than half of its inputs are true. For any finite set C of connectives we construct the corresponding W( C )-hierarchy. We derive some general conditions which guarantee that the W-hierarchy and the W( C )-hierarchy coincide levelwise. If C only contains the majority connective then the first levels of the hierarchies coincide. We use this to show that a variant of the parameterized vertex cover problem, the majority vertex cover problem, is W[1]-complete.
- Relation
- Theory of Computing Systems Vol. 46, Issue 2, p. 311-339
- Publisher Link
- http://dx.doi.org/10.1007/s00224-008-9138-6
- Date
- 2010
- Publisher
- Springer
- Keyword(s)
-
parameterized complexity;
W-hierarchy;
symmetric gates;
bounded weft circuits
- Resource Type
- journal article
- Identifier
- http://hdl.handle.net/1959.13/922189
- Identifier
- ISSN:1432-4350
- Reviewed
15 Visitors
16 Hits
0 Downloads
