On Maximizing Sums of Non-monotone Submodular and Linear Functions
We study the problem of Regularized Unconstrained SubmodularMaximization (RegularizedUSM) as defined by Bodek and Feldman (Maximizing sums of non-monotone submodular and linear functions: understanding the unconstrained case, arXiv:2204.03412 , 2022): given query access to a non-negative submodular...
Gespeichert in:
| Veröffentlicht in: | Algorithmica Jg. 86; H. 4; S. 1080 - 1134 |
|---|---|
| 1. Verfasser: | |
| Format: | Journal Article |
| Sprache: | Englisch |
| Veröffentlicht: |
New York
Springer US
01.04.2024
Springer Nature B.V |
| Schlagworte: | |
| ISSN: | 0178-4617, 1432-0541 |
| Online-Zugang: | Volltext |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| Zusammenfassung: | We study the problem of Regularized Unconstrained SubmodularMaximization (RegularizedUSM) as defined by Bodek and Feldman (Maximizing sums of non-monotone submodular and linear functions: understanding the unconstrained case,
arXiv:2204.03412
, 2022): given query access to a non-negative submodular function
f
:
2
N
→
R
≥
0
and a linear function
ℓ
:
2
N
→
R
over the same ground set
N
, output a set
T
⊆
N
approximately maximizing the sum
f
(
T
)
+
ℓ
(
T
)
. An algorithm is said to provide an
(
α
,
β
)
-approximation for RegularizedUSM if it outputs a set
T
such that
E
[
f
(
T
)
+
ℓ
(
T
)
]
≥
max
S
⊆
N
[
α
·
f
(
S
)
+
β
·
ℓ
(
S
)
]
. We also consider the setting where
S
and
T
are constrained to be independent in a given matroid, which we refer to as Regularized
Constrained
Submodular Maximization (RegularizedCSM). The special case of RegularizedCSM with monotone
f
has been extensively studied (Sviridenko et al. in Math Oper Res 42(4):1197–1218, 2017; Feldman in Algorithmica 83(3):853–878, 2021; Harshaw et al., in: International conference on machine learning, PMLR, 2634–2643, 2019), whereas we are aware of only one prior work that studies RegularizedCSM with non-monotone
f
(Lu et al. in Optimization 1–27, 2023), and that work constrains
ℓ
to be non-positive. In this work, we provide improved
(
α
,
β
)
-approximation algorithms for both RegularizedUSM and RegularizedCSM with non-monotone
f
. Specifically, we are the first to provide nontrivial
(
α
,
β
)
-approximations for RegularizedCSM where the sign of
ℓ
is unconstrained, and the
α
we obtain for RegularizedUSM improves over (Bodek and Feldman in Maximizing sums of non-monotone submodular and linear functions: understanding the unconstrained case,
arXiv:2204.03412
, 2022) for all
β
∈
(
0
,
1
)
. We also prove new inapproximability results for RegularizedUSM and RegularizedCSM, as well as 0.478-inapproximability for maximizing a submodular function where
S
and
T
are subject to a cardinality constraint, improving a 0.491-inapproximability result due to Oveis Gharan and Vondrak (in: Proceedings of the twenty-second annual ACM-SIAM symposium on discrete algorithms, SIAM, pp 1098–1116, 2011). |
|---|---|
| Bibliographie: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 14 |
| ISSN: | 0178-4617 1432-0541 |
| DOI: | 10.1007/s00453-023-01183-3 |