TY - JOUR
T1 - Warm-starting lower bound set computations for branch-and-bound algorithms for multi objective integer linear programs
AU - Forget, Nicolas Joseph
AU - Gadegaard, Sune Lauth
AU - Relund, Lars
PY - 2022/11/1
Y1 - 2022/11/1
N2 - In this paper we propose a generic branch-and-bound algorithm for solving multi-objective integer linear programming problems. In the recent literature, competitive frameworks has been proposed for bi-objective 0–1 problems, and many of these frameworks rely on the use of the linear relaxation to obtain lower bound sets. When increasing the number of objective functions, however, the polyhedral structure of the linear relaxation becomes more complex, and consequently requires more computational effort to obtain. In this paper we overcome this obstacle by speeding up the computations. To do so, in each branching node we use information available from its father node to warm-start a Bensons-like algorithm. We show that the proposed algorithm significantly reduces the CPU time of the framework on several different problem classes with three, four and five objective functions. Moreover, we point out difficulties that arise when non-binary integer variables are introduced in the models, and test our algorithm on problem that contains non-binary integer variables too.
AB - In this paper we propose a generic branch-and-bound algorithm for solving multi-objective integer linear programming problems. In the recent literature, competitive frameworks has been proposed for bi-objective 0–1 problems, and many of these frameworks rely on the use of the linear relaxation to obtain lower bound sets. When increasing the number of objective functions, however, the polyhedral structure of the linear relaxation becomes more complex, and consequently requires more computational effort to obtain. In this paper we overcome this obstacle by speeding up the computations. To do so, in each branching node we use information available from its father node to warm-start a Bensons-like algorithm. We show that the proposed algorithm significantly reduces the CPU time of the framework on several different problem classes with three, four and five objective functions. Moreover, we point out difficulties that arise when non-binary integer variables are introduced in the models, and test our algorithm on problem that contains non-binary integer variables too.
KW - Branch and bound
KW - Combinatorial optimization
KW - Linear relaxation
KW - Multiple objective programming
KW - Warm-starting
UR - http://www.scopus.com/inward/record.url?scp=85125127761&partnerID=8YFLogxK
U2 - 10.1016/j.ejor.2022.01.047
DO - 10.1016/j.ejor.2022.01.047
M3 - Journal article
AN - SCOPUS:85125127761
SN - 0377-2217
VL - 302
SP - 909
EP - 924
JO - European Journal of Operational Research
JF - European Journal of Operational Research
IS - 3
ER -