Title
A 1/2-approximation algorithm for maximizing a non-monotone weak-submodular function on a bounded integer lattice
Abstract
Maximizing non-monotone submodular functions is one of the most important problems in submodular optimization. Let $$\mathbf {B}=(B_1, B_2,\ldots , B_n)\in {\mathbb {Z}}_+^n$$ be an integer vector and $$[\mathbf { B}]=\{(x_1,\dots ,x_n) \in {\mathbb {Z}}_+^n: 0\le x_k \le B_k, \forall 1\le k\le n\}$$ be the set of all non-negative integer vectors not greater than $$\mathbf {B}$$. A function $$f:[\mathbf { B}] \rightarrow {\mathbb {R}}$$ is said to be weak-submodular if $$f(\mathbf {x}+\delta \mathbf {1}_k)-f(\mathbf {x})\ge f(\mathbf {y}+\delta \mathbf {1}_k)-f(\mathbf {y})$$ for any $$k\in \{1,\dots ,n\}$$, any pair of $$\mathbf {x}, \mathbf {y}\in [\mathbf { B}]$$ such that $$\mathbf {x}\le \mathbf {y}$$ and $$x_k =y_k$$, and any $$\delta \in {\mathbb {Z}}_+$$ satisfying $$\mathbf {y}+\delta \mathbf {1}_k\in [\mathbf { B}]$$. Here $$\mathbf {1}_k$$ is the vector with the kth component equal to 1 and each of the others equals to 0. In this paper we consider the problem of maximizing a non-monotone and non-negative weak-submodular function on the bounded integer lattice without any constraint. We present an randomized algorithm with an approximation guarantee $$\frac{1}{2}$$ for the problem.
Year
DOI
Venue
2020
10.1007/s10878-020-00558-4
Journal of Combinatorial Optimization
Keywords
DocType
Volume
Submodular, Non-monotone, Algorithm, Double greedy
Journal
39
Issue
ISSN
Citations 
4
1382-6905
0
PageRank 
References 
Authors
0.34
0
6
Name
Order
Citations
PageRank
Q. Q. Nong1476.24
Jiazhu Fang200.34
Suning Gong351.84
Ding-Zhu Du43497283.06
Yan Feng500.34
Xiaoying Qu600.34