Partial Convexification of General MIPs
DIKU-talk by Professor Marco Lübbecke, RWTH Aachen
Abstract:
Dantzig-Wolfe decomposition is well-known to provide strong dual bounds for specially structured mixed integer programs (MIPs) in practice. However, the method is not implemented in any state-of-the-art MIP solver: it needs tailoring to the particular problem; the decomposition must be determined from the typical bordered block-diagonal matrix structure; the resulting column generation subproblems must be solved efficiently; etc.
We provide a computational proof-of-concept that the process can be automated in principle, and that strong dual bounds can be obtained on general MIPs for which a solution by a decomposition has not been the first choice.
We perform an extensive computational study on the 0-1 dynamic knapsack problem (without block-diagonal structure) and on general MIPLIB2003 instances.
Our results support that Dantzig-Wolfe reformulation may hold more promise as a general-purpose tool than previously acknowledged by the research community.
Bio
Marco Lübbecke is Professor and Chair of Operations Research, at the RWTH Aachen University. His primary research interests comprise:
- Computational mixed integer programming
- Column generation and branch-and-price
- Combinatorial optimization
- Operations research
- Industrial applications (logistics, production)
- Geometrically motivated optimization problems