English
Related papers

Related papers: A problem equivalent to counting directed acyclic …

200 papers

Learning directed acyclic graphs (DAGs) from data is a challenging task both in theory and in practice, because the number of possible DAGs scales superexponentially with the number of nodes. In this paper, we study the problem of learning…

Machine Learning · Computer Science 2019-04-25 Hasan Manzour , Simge Küçükyavuz , Ali Shojaie

The displayed tree phylogenetic network model is shown to sit as a natural submodel of the graphical model associated to a directed acyclic graph (DAG). This representation allows to derive a number of results about the displayed tree…

Populations and Evolution · Quantitative Biology 2025-08-01 Seth Sullivant

Berwanger et al. show that for every graph $G$ of size $n$ and DAG-width $k$ there is a DAG decomposition of width $k$ and size $n^{O(k)}$. This gives a polynomial time algorithm for determining the DAG-width of a graph for any fixed $k$.…

Discrete Mathematics · Computer Science 2020-04-01 Saeed Akhoondian Amiri , Stephan Kreutzer , Roman Rabinovich

There has been a growing interest in causal learning in recent years. Commonly used representations of causal structures, including Bayesian networks and structural equation models (SEM), take the form of directed acyclic graphs (DAGs). We…

Machine Learning · Computer Science 2025-11-20 Pavel Rytir , Ales Wodecki , Jakub Marecek

Partial 1-trees are undirected graphs of treewidth at most one. Similarly, partial 1-DAGs are directed graphs of KellyWidth at most two. It is well-known that an undirected graph is a partial 1-tree if and only if it has no K_3 minor. In…

Combinatorics · Mathematics 2014-01-14 Shiva Kintali , Qiuyi Zhang

This paper explores the conditions for determining fixed nodes in structured networks, specifically focusing on directed acyclic graphs (DAGs). We introduce several necessary and sufficient conditions for determining fixed nodes in…

General Topology · Mathematics 2025-09-08 Nam-jin Park , Yeong-Ung Kim , Hyo-Sung Ahn

A finite non-increasing sequence of positive integers $d = (d_1\geq \cdots\geq d_n)$ is called a degree sequence if there is a graph $G = (V,E)$ with $V = \{v_1,\ldots,v_n\}$ and $deg(v_i)=d_i$ for $i=1,\ldots,n$. In that case we say that…

Combinatorics · Mathematics 2021-01-08 Atabey Kaygun

We prove that every oriented tree on $n$ vertices with bounded maximum degree appears as a spanning subdigraph of every directed graph on $n$ vertices with minimum semidegree at least $n/2+o(n)$. This can be seen as a directed graph…

Combinatorics · Mathematics 2026-05-20 Richard Mycroft , Tássio Naia

Let $s(n)$ be the minimum number of edges in a graph that contains every $n$-vertex tree as a subgraph. Chung and Graham [J. London Math. Soc. 1983] claim to prove that $s(n)\leqslant O(n\log n)$. We point out a mistake in their proof. The…

Combinatorics · Mathematics 2025-08-06 Neel Kaul , David R. Wood

We prove that for every set $S$ of vertices of a directed graph $D$, the maximum number of vertices in $S$ contained in a collection of vertex-disjoint cycles in $D$ is at least the minimum size of a set of vertices that hits all cycles…

Combinatorics · Mathematics 2026-02-26 Nathan Bowler , Ebrahim Ghorbani , Florian Gut , Raphael W. Jacobs , Florian Reich

We initiate the study of counting Markov Equivalence Classes (MEC) under logical constraints. MECs are equivalence classes of Directed Acyclic Graphs (DAGs) that encode the same conditional independence structure among the random variables…

Logic in Computer Science · Computer Science 2024-05-24 Davide Bizzaro , Luciano Serafini , Sagar Malhotra

The assumed causal relationships depicted in a DAG are interpreted using a set of rules called D-separation rules. Although these rules can be implemented automatically using standard software, at least a basic understanding of their…

Methodology · Statistics 2025-02-20 Fernando Pires Hartwig , Timothy Feeney , Neil Davies

The Minimum Path Cover problem on directed acyclic graphs (DAGs) is a classical problem that provides a clear and simple mathematical formulation for several applications in different areas and that has an efficient algorithmic solution. In…

Data Structures and Algorithms · Computer Science 2014-03-06 Niko Beerenwinkel , Stefano Beretta , Paola Bonizzoni , Riccardo Dondi , Yuri Pirola

A digraph that represents reasonably a scheduling problem should be a directed acyclic graph. Here down we shall deal with special kind of graded $DAGs$ named $KoDAGs$. For their definition and first primary properties see $ [1]$, where…

Combinatorics · Mathematics 2011-05-19 A. K. Kwaniewski

We show how to chain maximal exact matches (MEMs) between a query string $Q$ and a labeled directed acyclic graph (DAG) $G=(V,E)$ to solve the longest common subsequence (LCS) problem between $Q$ and $G$. We obtain our result via a new…

Data Structures and Algorithms · Computer Science 2023-07-06 Nicola Rizzo , Manuel Cáceres , Veli Mäkinen

The scheduling and schedulability analysis of real-time directed acyclic graph (DAG) task systems have received much recent attention. The DAG model can accurately represent intra-task parallelim and precedence constraints existing in many…

Operating Systems · Computer Science 2018-08-02 Zheng Dong , Cong Liu

The decycling number of a graph $G$ is the minimum number of vertices whose removal from $G$ results in an acyclic subgraph. It is known that determining the decycling number of a graph $G$ is equivalent to finding the maximum induced…

Combinatorics · Mathematics 2018-09-20 Jian Wang , Xirong Xu

Reconfiguration problems involve determining whether two given configurations can be transformed into each other under specific rules. The Token Sliding problem asks whether, given two different set of tokens on vertices of a graph $G$, we…

Data Structures and Algorithms · Computer Science 2026-03-26 Niranka Banerjee , Christian Engels , Duc A. Hoang

This paper explores the role of Directed Acyclic Graphs (DAGs) as a representation of conditional independence relationships. We show that DAGs offer polynomially sound and complete inference mechanisms for inferring conditional…

Artificial Intelligence · Computer Science 2013-04-10 Dan Geiger , Judea Pearl

The width $k$ of a directed acyclic graph (DAG) $G = (V, E)$ equals the largest number of pairwise non-reachable vertices. Computing the width dates back to Dilworth's and Fulkerson's results in the 1950s, and is doable in quadratic time in…

Data Structures and Algorithms · Computer Science 2021-06-25 Manuel Cáceres , Massimo Cairo , Brendan Mumey , Romeo Rizzi , Alexandru I. Tomescu