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This paper considers a fractional programming problem (P) which minimizes a ratio of quadratic functions subject to a two-sided quadratic constraint. As is well-known, the fractional objective function can be replaced by a parametric family…

Optimization and Control · Mathematics 2014-02-19 Van-Bong Nguyen , Ruey-Lin Sheu , Yong Xia

The complexity of graph homomorphism problems has been the subject of intense study. It is a long standing open problem to give a (decidable) complexity dichotomy theorem for the partition function of directed graph homomorphisms. In this…

Computational Complexity · Computer Science 2010-08-06 Jin-Yi Cai , Xi Chen

The determination of the computational complexity of multi-agent pathfinding on directed graphs (diMAPF) has been an open research problem for many years. While diMAPF has been shown to be polynomial for some special cases, only recently,…

Artificial Intelligence · Computer Science 2023-02-13 Bernhard Nebel

Symbolic regression (SR) is the task of discovering a symbolic expression that fits a given data set from the space of mathematical expressions. Despite the abundance of research surrounding the SR problem, there's a scarcity of works that…

Computational Complexity · Computer Science 2024-04-23 Jinglu Song , Qiang Lu , Bozhou Tian , Jingwen Zhang , Jake Luo , Zhiguang Wang

Combinatorial optimization algorithms for graph problems are usually designed afresh for each new problem with careful attention by an expert to the problem structure. In this work, we develop a new framework to solve any combinatorial…

The major challenge in designing a discriminative learning algorithm for predicting structured data is to address the computational issues arising from the exponential size of the output space. Existing algorithms make different assumptions…

Machine Learning · Computer Science 2010-06-29 Shankar Vembu

Sparse graphs and their associated matroids play an important role in rigidity theory, where they capture the combinatorics of generically rigid structures. We define a new family called {\bf graded sparse graphs}, arising from generically…

Combinatorics · Mathematics 2011-11-10 Audrey Lee , Ileana Streinu , Louis Theran

We consider two CSP problems: the first CSP encodes 2D Sperner's lemma for the standard triangulation of the right triangle on $n^2$ small triangles; the second CSP encodes the fact that it is impossible to match cells of $n \times n$…

Computational Complexity · Computer Science 2014-12-04 Dmitry Itsykson , Anna Malova , Vsevolod Oparin , Dmitry Sokolov

In this paper we generalize N-fold integer programs and two-stage integer programs with N scenarios to N-fold 4-block decomposable integer programs. We show that for fixed blocks but variable N, these integer programs are polynomial-time…

Optimization and Control · Mathematics 2015-05-14 Raymond Hemmecke , Matthias Köppe , Robert Weismantel

We prove a complexity dichotomy theorem for all non-negative weighted counting Constraint Satisfaction Problems (CSP). This caps a long series of important results on counting problems including unweighted and weighted graph homomorphisms…

Computational Complexity · Computer Science 2010-12-30 Jin-Yi Cai , Xi Chen , Pinyan Lu

Neural models have shown promise in solving NP-hard graph combinatorial optimization (CO) problems. Once trained, they offer fast inference and reasonably high-quality solutions for in-distribution testing instances, but they generally fall…

Machine Learning · Computer Science 2025-11-26 Jialiang Li , Weitong Chen , Mingyu Guo

A decision problem is called parameterized if its input is a pair of strings. One of these strings is referred to as a parameter. The problem: given a propositional logic program P and a non-negative integer k, decide whether P has a stable…

Logic in Computer Science · Computer Science 2007-05-23 Zbigniew Lonc , Miroslaw Truszczynski

We present a learning-based approach to computing solutions for certain NP-hard problems. Our approach combines deep learning techniques with useful algorithmic elements from classic heuristics. The central component is a graph…

Machine Learning · Computer Science 2018-10-26 Zhuwen Li , Qifeng Chen , Vladlen Koltun

A central question in computer science and statistics is whether efficient algorithms can achieve the information-theoretic limits of statistical problems. Many computational-statistical tradeoffs have been shown under average-case…

Computational Complexity · Computer Science 2025-07-18 Guy Blanc , Caleb Koch , Carmen Strassle , Li-Yang Tan

We study the complexity of the Distributed Constraint Satisfaction Problem (DCSP) on a synchronous, anonymous network from a theoretical standpoint. In this setting, variables and constraints are controlled by agents which communicate with…

Data Structures and Algorithms · Computer Science 2021-01-25 Silvia Butti , Victor Dalmau

We study provably effective and efficient data reduction for a class of NP-hard graph modification problems based on vertex degree properties. We show fixed-parameter tractability for NP-hard graph completion (that is, edge addition) cases…

Discrete Mathematics · Computer Science 2016-04-13 Vincent Froese , André Nichterlein , Rolf Niedermeier

The fundamental tension between availability and consistency shapes the design of distributed storage systems. Classical results capture extreme points of this trade-off: the CAP theorem shows that strong models like linearizability…

Distributed, Parallel, and Cluster Computing · Computer Science 2025-10-29 Hagit Attiya , Constantin Enea , Enrique Román-Calvo

As it follows from G\"odel's incompleteness theorems, any consistent formal system of axioms and rules of inference should imply a true unprovable statement. Actually, this fundamental principle can be efficiently applicable in…

Data Structures and Algorithms · Computer Science 2020-11-25 Roman Galay , Daniil Kalistratov

Given a graph $G$, and terminal vertices $s$ and $t$, the TRACKING PATHS problem asks to compute a minimum number of vertices to be marked as trackers, such that the sequence of trackers encountered in each s-t path is unique. TRACKING…

Data Structures and Algorithms · Computer Science 2020-02-19 Pratibha Choudhary

The synthesis of classical Computational Complexity Theory with Recursive Analysis provides a quantitative foundation to reliable numerics. Here the operators of maximization, integration, and solving ordinary differential equations are…

Numerical Analysis · Computer Science 2012-11-22 Akitoshi Kawamura , Norbert Th. Müller , Carsten Rösnick , Martin Ziegler