Given a graph G and an integer k, the maximum edge subgraph problem consists in finding a k-vertex subset of G such that the number of edges within the subset is maximum. This NP-hard problem arises in the analysis of cohesive subgroups in social networks. In this work we study the polytope P(G,k) associated with a straightforward integer programming formulation of the maximum edge subgraph problem. We characterize the graph generated by P(G,k) and give a tight bound on its diameter. We give a complete description of P(K1n,k), where K1n is the star on n+1 vertices, and we conjecture a complete description of P(mK2,k), where mK2 is the graph composed by m disjoint edges. Finally, we introduce three families of facet-inducing inequalities for P(G,k), which generalize known families of valid inequalities for this polytope. © 2011 Elsevier B.V.
Documento: | Artículo |
Título: | Combinatorial properties and further facets of maximum edge subgraph polytopes |
Autor: | Marenco, J.; Saban, D. |
Filiación: | Sciences Institute, National University of General Sarmiento, Argentina Computer Science Dept., FCEN, University of Buenos Aires, Argentina |
Palabras clave: | Diameter of polytopes; Facets; Maximum edge subgraph problem |
Año: | 2011 |
Volumen: | 37 |
Número: | C |
Página de inicio: | 303 |
Página de fin: | 308 |
DOI: | http://dx.doi.org/10.1016/j.endm.2011.05.052 |
Título revista: | Electronic Notes in Discrete Mathematics |
Título revista abreviado: | Electron. Notes Discrete Math. |
ISSN: | 15710653 |
Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_15710653_v37_nC_p303_Marenco |