  In this paper, we present a multi-parent memetic algorithm (denoted by MPM)
for solving the classic Linear Ordering Problem (LOP). The MPM algorithm
integrates in particular a multi-parent recombination operator for generating
offspring solutions and a distance-and-quality based criterion for pool
updating. Our MPM algorithm is assessed on 8 sets of 484 widely used LOP
instances and compared with several state-of-the-art algorithms in the
literature, showing the efficacy of the MPM algorithm. Specifically, for the
255 instances whose optimal solutions are unknown, the MPM is able to detect
better solutions than the previous best-known ones for 66 instances, while
matching the previous best-known results for 163 instances. Furthermore, some
additional experiments are carried out to analyze the key elements and
important parameters of MPM.
