@techreport{Jansen98-1-006,
TITLE = {A new characterization for parity graphs and a coloring problem with costs},
AUTHOR = {Jansen, Klaus},
LANGUAGE = {eng},
NUMBER = {MPI-I-1998-1-006},
INSTITUTION = {Max-Planck-Institut f{\"u}r Informatik},
ADDRESS = {Saarbr{\"u}cken},
YEAR = {1998},
DATE = {1998},
ABSTRACT = {In this paper, we give a characterization for parity graphs. A graph is a parity graph, if and only if for every pair of vertices all minimal chains joining them have the same parity. We prove that $G$ is a parity graph, if and only if the cartesian product $G \times K_2$ is a perfect graph. Furthermore, as a consequence we get a result for the polyhedron corresponding to an integer linear program formulation of a coloring problem with costs. For the case that the costs $k_{v,3} = k_{v,c}$ for each color $c \ge 3$ and vertex $v \in V$, we show that the polyhedron contains only integral $0 / 1$ extrema if and only if the graph $G$ is a parity graph.},
TYPE = {Research Report / Max-Planck-Institut für Informatik},
}