51. Two-stage submodular maximization problem beyond nonnegative and monotone
- Author
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Hong Chang, Xiaoyan Zhang, Zhicheng Liu, Donglei Du, and Ran Ma
- Subjects
Combinatorics ,Submodular maximization ,Mathematics (miscellaneous) ,Monotone polygon ,Computer science ,Stage (hydrology) ,Computer Science Applications - Abstract
We consider a two-stage submodular maximization problem subject to a cardinality constraint andkmatroid constraints, where the objective function is the expected difference of a nonnegative monotone submodular function and a nonnegative monotone modular function. We give two bi-factor approximation algorithms for this problem. The first is a deterministic$\left( {{1 \over {k + 1}}\left( {1 - {1 \over {{e^{k + 1}}}}} \right),1} \right)$-approximation algorithm, and the second is a randomized$\left( {{1 \over {k + 1}}\left( {1 - {1 \over {{e^{k + 1}}}}} \right) - \varepsilon ,1} \right)$-approximation algorithm with improved time efficiency.
- Published
- 2021