Title
Revisiting Modified Greedy Algorithm for Monotone Submodular Maximization with a Knapsack Constraint
Abstract
AbstractMonotone submodular maximization with a knapsack constraint is NP-hard. Various approximation algorithms have been devised to address this optimization problem. In this paper, we revisit the widely known modified greedy algorithm. First, we show that this algorithm can achieve an approximation factor of 0.405, which significantly improves the known factors of 0.357 given by Wolsey and (1-1/e)/2\approx 0.316 given by Khuller et al. More importantly, our analysis closes a gap in Khuller et al.'s proof for the extensively mentioned approximation factor of (1-1/\sqrte )\approx 0.393 in the literature to clarify a long-standing misconception on this issue. Second, we enhance the modified greedy algorithm to derive a data-dependent upper bound on the optimum. We empirically demonstrate the tightness of our upper bound with a real-world application. The bound enables us to obtain a data-dependent ratio typically much higher than 0.405 between the solution value of the modified greedy algorithm and the optimum. It can also be used to significantly improve the efficiency of algorithms such as branch and bound.
Year
DOI
Venue
2021
10.1145/3447386
Proceedings of the ACM on Measurement and Analysis of Computing Systems
DocType
Volume
Issue
Journal
5
1
Citations 
PageRank 
References 
0
0.34
0
Authors
6
Name
Order
Citations
PageRank
Jing Tang111.04
Xueyan Tang200.34
Andrew Lim393789.78
Kai Han400.68
Chongshou Li500.34
Junsong Yuan63703187.68