Title
Intermediate integer programming representations using value disjunctions
Abstract
We introduce a general technique for creating an extended formulation of a mixed-integer program. We classify the integer variables into blocks, each of which generates a finite set of vector values. The extended formulation is constructed by creating a new binary variable for each generated value. Initial experiments show that the extended formulation can have a more compact complete description than the original formulation. We prove that, using this reformulation technique, the facet description decomposes into one ''linking polyhedron'' per block and the ''aggregated polyhedron''. Each of these polyhedra can be analyzed separately. For the case of identical coefficients in a block, we provide a complete description of the linking polyhedron and a polynomial-time separation algorithm. Applied to the knapsack with a fixed number of distinct coefficients, this theorem provides a complete description in an extended space with a polynomial number of variables. On the basis of this theory, we propose a new branching scheme that analyzes the problem structure. It is designed to be applied in those subproblems of hard integer programs where LP-based techniques do not provide good branching decisions. Preliminary computational experiments show that it is successful for some benchmark problems of multi-knapsack type.
Year
DOI
Venue
2008
10.1016/j.disopt.2006.12.003
Discrete Optimization
Keywords
Field
DocType
original formulation,compact complete description,aggregated polyhedron,branch-and-cut algorithms,polyhedral combinatorics,extended space,extended formulations,fixed number,complete description,mixed-integer programming,general technique,extended formulation,lp-based technique,facet description decomposes,value disjunction,intermediate integer programming representation,mixed integer programming,branch and cut,computer experiment,polynomial time
Integer,Discrete mathematics,Mathematical optimization,Polynomial,Polyhedron,Branch and cut,Branch and price,Integer programming,Knapsack problem,Mathematics,Polyhedral combinatorics
Journal
Volume
Issue
ISSN
5
2
Discrete Optimization
Citations 
PageRank 
References 
5
0.55
15
Authors
3
Name
Order
Citations
PageRank
Matthias KöPpe119120.95
Quentin Louveaux218914.83
Robert Weismantel396490.05