A column generation based approach is proposed for solving the cluster-wise regression problem. The proposed strategy relies firstly on several efficient heuristic strategies to insert columns into the restricted master problem. If these heuristics fail to identify an improving column, an...

The single machine sequencing problem is considered in which there are precedence constraints on the jobs. The objective is to minimize the sum of weighted completion times. A lower bound is obtained by successively performing a Lagrangean relaxation of appropriate constraints. Each Lagrange...