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Related papers: Unit Mixed Interval Graphs

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We give a complete characterization of mixed unit interval graphs, the intersection graphs of closed, open, and half-open unit intervals of the real line. This is a proper superclass of the well known unit interval graphs. Our result solves…

Combinatorics · Mathematics 2014-06-12 Felix Joos

The class of intersection bigraphs of unit intervals of the real line whose ends may be open or closed is called a class of mixed unit interval bigraphs. This class of bigraphs is a strict superclass of the class of unit interval bigraphs.…

Discrete Mathematics · Computer Science 2026-05-27 Ashok Kumar Das , Rajkamal Sahu , Amina Khatun

We describe the missing class of the hierarchy of mixed unit interval graphs, generated by the intersection graphs of closed, open and one type of half-open intervals of the real line. This class lies strictly between unit interval graphs…

Discrete Mathematics · Computer Science 2017-02-22 Alexandre Talon , Jan Kratochvíl

Interval graphs, intersection graphs of segments on a real line (intervals), play a key role in the study of algorithms and special structural properties. Unit interval graphs, their proper subclass, where each interval has a unit length,…

Data Structures and Algorithms · Computer Science 2026-02-19 Jan Kratochvíl , Tomáš Masařík , Jana Novotná

Intersection graphs are very important in both theoretical as well as application point of view. Depending on the geometrical representation, different type of intersection graphs are defined. Among them interval, circular-arc, permutation,…

Discrete Mathematics · Computer Science 2014-04-23 Madhumangal Pal

In a paired threshold graph, each vertex has a weight, and two vertices are adjacent if their weight sum is large enough and their weight difference is small enough. It generalizes threshold graphs and unit interval graphs, both very well…

Data Structures and Algorithms · Computer Science 2019-10-01 Guozhen Rong , Yixin Cao , Jianxin Wang

It is shown that shift graphs can be realized as disjointness graphs of 1-intersecting curves in the plane. This implies that the latter class of graphs is not $\chi$-bounded.

Combinatorics · Mathematics 2018-02-28 Torsten Mütze , Bartosz Walczak , Veit Wiechert

In this survey, we have attempted to show some developmental milestones on the characterizations of intersection graphs of hypergraphs. The theory of intersection graphs of hypergraphs has been a classical topic in the theory of special…

Combinatorics · Mathematics 2025-07-02 Ranjan N. Naik

We unify several seemingly different graph and digraph classes under one umbrella. These classes are all broadly speaking different generalizations of interval graphs, and include, in addition to interval graphs, also adjusted interval…

Discrete Mathematics · Computer Science 2018-06-28 Pavol Hell , Jing Huang , Ross M. McConnell , Arash Rafiey

There is a well-documented research programme on graph operators which addresses questions such as `Which graphs appear as images of graphs?'; `Which graphs are fixed under the operator?'; `What happens if the operator is iterated?' In this…

Combinatorics · Mathematics 2023-03-14 Christo Kriel , Eunice Mphako-Banda

Characterisations of interval graphs, comparability graphs, co-comparability graphs, permutation graphs, and split graphs in terms of linear orderings of the vertex set are presented. As an application, it is proved that interval graphs,…

Discrete Mathematics · Computer Science 2011-10-05 David R. Wood

In this note we give a combinatorial characterization of all the unmixed bipartite graphs.

Combinatorics · Mathematics 2011-04-05 Rafael H. Villarreal

Interval graphs and interval orders are deeply linked. In fact, edges of an interval graphs represent the incomparability relation of an interval order, and in general, of different interval orders. The question about the conditions under…

Combinatorics · Mathematics 2023-01-03 Marta Fiori-Carones , Alberto Marcone

We study experimentation under endogenous network interference. Interference patterns are mediated by an endogenous graph, where edges can be formed or eliminated as a result of treatment. We show that conventional estimators are biased in…

Methodology · Statistics 2026-01-21 Wenshuo Wang , Edvard Bakhitov , Dominic Coey

A graph is reconstructible if it is determined up to isomorphism by the multiset of its proper induced subgraphs. The reconstruction conjecture postulates that every graph of order at least 3 is reconstructible. We show that interval graphs…

Combinatorics · Mathematics 2026-05-13 Irene Heinrich , Masashi Kiyomi , Yota Otachi , Pascal Schweitzer

A unit disk graph is the intersection graph of disks of equal radii in the plane. The class of unit disk graphs is hereditary, and therefore admits a characterization in terms of minimal forbidden induced subgraphs. In spite of quite active…

Combinatorics · Mathematics 2016-02-29 Aistis Atminas , Viktor Zamaraev

The class of 2-interval graphs has been introduced for modelling scheduling and allocation problems, and more recently for specific bioinformatic problems. Some of those applications imply restrictions on the 2-interval graphs, and justify…

Discrete Mathematics · Computer Science 2008-02-04 Philippe Gambette , Stéphane Vialette

A \emph{mixed interval graph} is an interval graph that has, for every pair of intersecting intervals, either an arc (directed arbitrarily) or an (undirected) edge. We are particularly interested in scenarios where edges and arcs are…

Discrete Mathematics · Computer Science 2024-08-09 Grzegorz Gutowski , Konstanty Junosza-Szaniawski , Felix Klesen , Paweł Rzążewski , Alexander Wolff , Johannes Zink

We introduce a variation of interval graphs, called veto interval (VI) graphs. A VI graph is represented by a set of closed intervals, each containing a point called a veto mark. The edge $ab$ is in the graph if the intervals corresponding…

We work out the graph limit theory for dense interval graphs. The theory developed departs from the usual description of a graph limit as a symmetric function $W(x,y)$ on the unit square, with $x$ and $y$ uniform on the interval $(0,1)$.…

Combinatorics · Mathematics 2011-02-15 Persi Diaconis , Susan Holmes , Svante Janson
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