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View article: Treewidth is NP-Complete on Cubic Graphs
Treewidth is NP-Complete on Cubic Graphs Open
In this paper, we show that Treewidth is NP-complete for cubic graphs, thereby improving the result by Bodlaender and Thilikos from 1997 that Treewidth is NP-complete on graphs with maximum degree at most 9. We add a new and simpler proof …
View article: Parameterized Critical Node Cut Revisited
Parameterized Critical Node Cut Revisited Open
Given a graph $G$ and integers $k, x \geq 0$, the Critical Node Cut problem asks whether it is possible to delete at most $k$ vertices from $G$ such that the number of remaining pairs of connected vertices is at most $x$. This problem gene…
View article: Density of Traceable Graphs
Density of Traceable Graphs Open
We establish tight lower and upper bounds on the number of edges in traceable graphs in several classes of dense graphs. A graph is traceable if it has a Hamiltonian path. We show that the bound is: - quadratic for the class of graphs of b…
View article: Exact Algorithms for Multiagent Path Finding with Communication Constraints on Tree-Like Structures
Exact Algorithms for Multiagent Path Finding with Communication Constraints on Tree-Like Structures Open
Consider the scenario where multiple agents have to move in an optimal way through a network, each one towards their ending position, and while avoiding collisions. By optimal, we mean as fast as possible, which is evaluated by a measure k…
View article: Balanced and Fair Partitioning of Friends
Balanced and Fair Partitioning of Friends Open
In the recently introduced model of fair partitioning of friends, there is a set of agents located on the vertices of an underlying graph that indicates the friendships between the agents. The task is to partition the graph into k balanced…
View article: Solving Multiagent Path Finding on Highly Centralized Networks
Solving Multiagent Path Finding on Highly Centralized Networks Open
The Mutliagent Path Finding (MAPF) problem consists of identifying the trajectories that a set of agents should follow inside a given network in order to reach their desired destinations as soon as possible, but without colliding with each…
View article: Balanced and Fair Partitioning of Friends
Balanced and Fair Partitioning of Friends Open
In the recently introduced model of fair partitioning of friends, there is a set of agents located on the vertices of an underlying graph that indicates the friendships between the agents. The task is to partition the graph into $k$ balanc…
View article: Practical approach to $2$-Euclidean Preferences
Practical approach to $2$-Euclidean Preferences Open
An election is a pair $(C,V)$ of candidates and voters. Each vote is a ranking (permutation) of the candidates. An election is $d$-Euclidean if there is an embedding of both candidates and voters into $\mathbb{R}^d$ such that voter $v$ pre…
View article: Exact Algorithms for Distance to Unique Vertex Cover
Exact Algorithms for Distance to Unique Vertex Cover Open
Horiyama et al. (AAAI 2024) studied the problem of generating graph instances that possess a unique minimum vertex cover under specific conditions. Their approach involved pre-assigning certain vertices to be part of the solution or exclud…
View article: Traffic-Oblivious Multi-Commodity Flow Network Design
Traffic-Oblivious Multi-Commodity Flow Network Design Open
We consider the Minimum Multi-Commodity Flow Subgraph (MMCFS) problem: given a directed graph G with edge capacities cap and a retention ratio α ∈ (0,1), find an edge-wise minimum subgraph G' ⊆ G such that for all traffic matrices T routab…
View article: Solving Multiagent Path Finding on Highly Centralized Networks
Solving Multiagent Path Finding on Highly Centralized Networks Open
The Mutliagent Path Finding (MAPF) problem consists of identifying the trajectories that a set of agents should follow inside a given network in order to reach their desired destinations as soon as possible, but without colliding with each…
View article: Exact Algorithms for Multiagent Path Finding with Communication Constraints on Tree-Like Structures
Exact Algorithms for Multiagent Path Finding with Communication Constraints on Tree-Like Structures Open
Consider the scenario where multiple agents have to move in an optimal way through a network, each one towards their ending position while avoiding collisions. By optimal, we mean as fast as possible, which is evaluated by a measure known …
View article: On the Complexity of Target Set Selection in Simple Geometric Networks
On the Complexity of Target Set Selection in Simple Geometric Networks Open
We study the following model of disease spread in a social network. At first, all individuals are either infected or healthy. Next, in discrete rounds, the disease spreads in the network from infected to healthy individuals such that a hea…
View article: FCKT: Fine-Grained Cross-Task Knowledge Transfer with Semantic Contrastive Learning for Targeted Sentiment Analysis
FCKT: Fine-Grained Cross-Task Knowledge Transfer with Semantic Contrastive Learning for Targeted Sentiment Analysis Open
In this paper, we address the task of targeted sentiment analysis , which involves two sub-tasks, i.e., identifying specific aspects from reviews and determining their corresponding senti-ments. Aspect extraction forms the foundation for s…
View article: Equitable Connected Partition and Structural Parameters Revisited: N-fold Beats Lenstra
Equitable Connected Partition and Structural Parameters Revisited: N-fold Beats Lenstra Open
We study the Equitable Connected Partition (ECP for short) problem, where we are given a graph G=(V,E) together with an integer p, and our goal is to find a partition of V into p parts such that each part induces a connected sub-graph of G…
View article: Individual Rationality in Topological Distance Games is Surprisingly Hard
Individual Rationality in Topological Distance Games is Surprisingly Hard Open
In the recently introduced topological distance games, strategic agents need to be assigned to a subset of vertices of a topology. In the assignment, the utility of an agent depends on both the agent's inherent utilities for other agents a…
View article: Exact Algorithms and Lowerbounds for Multiagent Path Finding: Power of Treelike Topology
Exact Algorithms and Lowerbounds for Multiagent Path Finding: Power of Treelike Topology Open
In the Multiagent Path Finding (MAPF for short) problem, we focus on efficiently finding non-colliding paths for a set of k agents on a given graph G, where each agent seeks a path from its source vertex to a target. An important measure o…
View article: Baby PIH: Parameterized Inapproximability of Min CSP
Baby PIH: Parameterized Inapproximability of Min CSP Open
The Parameterized Inapproximability Hypothesis (PIH) is the analog of the PCP theorem in the world of parameterized complexity. It asserts that no FPT algorithm can distinguish a satisfiable 2CSP instance from one which is only (1-ε)-satis…
View article: Exact Algorithms and Lowerbounds for Multiagent Pathfinding: Power of Treelike Topology
Exact Algorithms and Lowerbounds for Multiagent Pathfinding: Power of Treelike Topology Open
In the Multiagent Path Finding problem (MAPF for short), we focus on efficiently finding non-colliding paths for a set of $k$ agents on a given graph $G$, where each agent seeks a path from its source vertex to a target. An important measu…
View article: Maximizing Social Welfare in Score-Based Social Distance Games
Maximizing Social Welfare in Score-Based Social Distance Games Open
Social distance games have been extensively studied as a coalition formation model where the utilities of agents in each coalition were captured using a utility function $u$ that took into account distances in a given social network. In th…
View article: High-Multiplicity Fair Allocation Using Parametric Integer Linear Programming
High-Multiplicity Fair Allocation Using Parametric Integer Linear Programming Open
Using insights from parametric integer linear programming, we improve the work of Bredereck et al. [Proc. ACM EC 2019] on high-multiplicity fair allocation. Answering an open question from their work, we proved that the problem of finding …
View article: On the Complexity of Target Set Selection in Simple Geometric Networks
On the Complexity of Target Set Selection in Simple Geometric Networks Open
We study the following model of disease spread in a social network. At first, all individuals are either infected or healthy. Next, in discrete rounds, the disease spreads in the network from infected to healthy individuals such that a hea…
View article: Maximizing Social Welfare in Score-Based Social Distance Games
Maximizing Social Welfare in Score-Based Social Distance Games Open
Social distance games have been extensively studied as a coalition formation\nmodel where the utilities of agents in each coalition were captured using a\nutility function u that took into account distances in a given social network.\nIn t…
View article: The Parameterized Complexity of Network Microaggregation
The Parameterized Complexity of Network Microaggregation Open
Microaggregation is a classical statistical disclosure control technique which requires the input data to be partitioned into clusters while adhering to specified size constraints. We provide novel exact algorithms and lower bounds for the…
View article: Fine-grained view on bribery for group identification
Fine-grained view on bribery for group identification Open
Given a set of agents qualifying or disqualifying each other, group identification is the task of identifying a socially qualified subgroup of agents. Social qualification depends on the specific rule used to aggregate individual qualifica…
View article: Host Community Respecting Refugee Housing
Host Community Respecting Refugee Housing Open
We propose a novel model for refugee housing respecting the preferences of the accepting community and refugees themselves. In particular, we are given a topology representing the local community, a set of inhabitants occupying some vertic…
View article: Treewidth is NP-Complete on Cubic Graphs (and related results)
Treewidth is NP-Complete on Cubic Graphs (and related results) Open
In this paper, we give a very simple proof that Treewidth is NP-complete; this proof also shows NP-completeness on the class of co-bipartite graphs. We then improve the result by Bodlaender and Thilikos from 1997 that Treewidth is NP-compl…
View article: Treewidth Is NP-Complete on Cubic Graphs
Treewidth Is NP-Complete on Cubic Graphs Open
In this paper, we show that Treewidth is NP-complete for cubic graphs, thereby improving the result by Bodlaender and Thilikos from 1997 that Treewidth is NP-complete on graphs with maximum degree at most 9. We add a new and simpler proof …
View article: High-multiplicity N-fold IP via configuration LP
High-multiplicity N-fold IP via configuration LP Open
N -fold integer programs (IPs) form an important class of block-structured IPs for which increasingly fast algorithms have recently been developed and successfully applied. We study high-multiplicity N -fold IPs, which encode IPs succinctl…