论文标题
有效的可变深度本地搜索预算的最大覆盖率问题
Effective Variable Depth Local Search for the Budgeted Maximum Coverage Problem
论文作者
论文摘要
我们解决了预算的最大覆盖范围问题(BMCP),这是标准0-1背包问题和设定盖问题的自然且更实用的扩展。给定具有非负权重的元素,n个具有非负成本的要素的子集和总预算,BMCP旨在选择某些子集,以使所选子集的总成本不超过预算,并且相关元素的总权重最大化。在本文中,我们为BMCP提出了可变的深度本地搜索算法(VDLS)。 VDL首先通过贪婪算法生成初始解决方案,然后通过部分深度优先搜索方法迭代地改善解决方案,该方法可以通过同时更改多个子集的状态(或不选择)来改善解决方案。这种方法使VDL可以广泛,深入地探索解决方案空间,并产生高质量的解决方案。我们进一步提出了一个邻居结构来提高算法性能,也就是说,如果它们至少具有一个共同的相关元素,则两个子集都有邻居关系。通过应用邻居结构,VDL可以调整所选子集,同时丢失尽可能少的覆盖元素。由于现有的BMCP基准仅具有简单的结构和小规模,因此我们设计了60个具有相对较大的尺度和复杂结构的新实例,以丰富BMCP实例的多样性。在30个公共实例和60个新实例上,我们设计的实验结果表明,对于BMCP,VDL显着优于现有的启发式启发式和一般CPLEX精确求解器。
We address the Budgeted Maximum Coverage Problem (BMCP), which is a natural and more practical extension of the standard 0-1 knapsack problem and the set cover problem. Given m elements with nonnegative weights, n subsets of elements with nonnegative costs, and a total budget, BMCP aims to select some subsets such that the total cost of selected subsets does not exceed the budget, and the total weight of associated elements is maximized. In this paper, we propose a variable depth local search algorithm (VDLS) for the BMCP. VDLS first generates an initial solution by a greedy algorithm, then iteratively improves the solution through a partial depth-first search method, that can improve the solution by simultaneously changing the states (selected or not) of multiple subsets. Such method allows VDLS to explore the solution space widely and deeply, and to yield high-quality solutions. We further propose a neighbour structure to boost the algorithm performance, that is, both subsets have a neighbour relation if they have at least one common associated element. By applying the neighbour structure, VDLS can adjust the selected subsets while losing as few covered elements as possible. Since the existing BMCP benchmarks only have simple structures and small scales, we design 60 new instances with relatively large scales and complex structures to enrich the diversity of the BMCP instances. Experimental results on 30 public instances and 60 new instances we designed demonstrate that VDLS significantly outperforms the existing heuristic and the general CPLEX exact solver, for the BMCP.