When scheduling a round robin tournament (RRT) a Home-Away-Pattern (HAP) set defines for each team i and each period p whether i plays at home or away in p. So far the complexity of the decision problem whether a RRT can be arranged based on a given HAP set or not is open. We give a necessary...

A single round robin tournament (RRT) consists of a set T of n teams (n even) and a set P of n - 1 periods. The teams have to be scheduled such that each team plays exactly once against each other team and such that each team plays exactly once per period. In order to establish fairness among...

We study round-robin tournaments for 2n teams. Here n is either interpreted as the number of clubs, each having two teams, or the number of strength groups with two teams each. For even n we give a construction of a Single round-robin tournament for 2n teams with 2n - 2 breaks, where the teams...

In general scheduling a sports league is a difficult combinatorial optimization problem. We study some variants of round robin tournaments and analyze the relationship with the planar three index assignment problem. The complexity of scheduling a round robin tournaments is settled by a reduction...