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Related papers: Dimension of Restricted Classes of Interval Orders

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In general, representations of interval orders may use an arbitrary set of interval lengths. We can define subclasses of interval orders by restricting the allowable lengths of intervals. Motivated by a recent paper of Keller, Trenk, and…

Combinatorics · Mathematics 2024-11-13 Csaba Biro , Sida Wan

A poset $P = (X,\prec)$ has an interval representation if each $x \in X$ can be assigned a real interval $I_x$ so that $x \prec y$ in $P$ if and only if $I_x$ lies completely to the left of $I_y$. Such orders are called \emph{interval…

Combinatorics · Mathematics 2017-07-26 Simona Boyadzhiyska , Garth Isaak , Ann N Trenk

We study poset limits given by sequences of finite interval orders or, as a special case, finite semiorders. In the interval order case, we show that every such limit can be represented by a probability measure on the space of closed…

Combinatorics · Mathematics 2011-04-08 Svante Janson

A poset $P = (X,\prec)$ is a unit OC interval order if there exists a representation that assigns an open or closed real interval $I(x)$ of unit length to each $x \in P$ so that $x \prec y$ in $P$ precisely when each point of $I(x)$ is less…

Combinatorics · Mathematics 2015-01-27 Alan Shuchat , Randy Shull , Ann Trenk

In this paper we combine ideas from tolerance orders with recent work on OC interval orders. We consider representations of posets by unit intervals $I_v$ in which the interval endpoints ($L(v)$ and $R(v)$) may be open or closed as well as…

Combinatorics · Mathematics 2017-07-26 Alan Shuchat , Randy Shull , Ann N Trenk

A poset $P= (X, \prec)$ has an interval representation if each $x \in X$ can be assigned a real interval $I_x$ so that $x \prec y$ in $P$ if and only if $I_x$ lies completely to the left of $I_y$. Such orders are called \emph{interval…

Combinatorics · Mathematics 2018-04-11 Simona Boyadzhiyska , Garth Isaak , Ann Trenk

The Dushnik--Miller dimension of a poset $P$ is the least $d$ for which $P$ can be embedded into a product of $d$ chains. Lewis and Souza showed that the dimension of the divisibility order on the interval of integers $[N/\kappa, N]$ is…

Combinatorics · Mathematics 2023-11-15 Milan Haiman

Dimension is a standard and well-studied measure of complexity of posets. Recent research has provided many new upper bounds on the dimension for various structurally restricted classes of posets. Bounded dimension gives a succinct…

Combinatorics · Mathematics 2017-05-26 William T. Trotter , Bartosz Walczak

The interval count problem, a classical question in the study of interval orders, was introduced by Ronald Graham in the 1980s. This problem asks: given an interval order $P$, what is the minimum number of distinct interval lengths required…

Combinatorics · Mathematics 2024-11-19 Csaba Biró , André E. Kézdy , Jenő Lehel

Motivated by the study of the dimension of random posets, it was conjectured by Bollob\'as and Brightwell in 1997 that if $P$ is a finite poset whose cover graph contains at most one cycle then its order dimension is at most $3$. In this…

Combinatorics · Mathematics 2025-05-23 Antoine Abram , Adrien Segovia

Joret et al. proved that posets with cover graphs of treewidth at most 2 have dimension at most 1276. Their proof is long and very complex. We give a short and much simpler proof that the dimension of such posets is at most 12.

Combinatorics · Mathematics 2019-06-18 Michał T. Seweryn

The dimension of a partially ordered set $P$ (poset for short) is the least positive integer $d$ such that $P$ is isomorphic to a subposet of $\mathbb{R}^d$ with the natural product order. Dimension is arguably the most widely studied…

Combinatorics · Mathematics 2025-12-19 Heather Smith Blake , Jędrzej Hodor , Piotr Micek , Michał T. Seweryn , William T. Trotter

The dimension is a key measure of complexity of partially ordered sets. Small dimension allows succinct encoding. Indeed if $P$ has dimension $d$, then to know whether $x \leq y$ in $P$ it is enough to check whether $x\leq y$ in each of the…

Combinatorics · Mathematics 2019-12-12 Stefan Felsner , Tamás Mészáros , Piotr Micek

In 1977, Trotter and Moore proved that a poset has dimension at most $3$ whenever its cover graph is a forest, or equivalently, has treewidth at most $1$. On the other hand, a well-known construction of Kelly shows that there are posets of…

Combinatorics · Mathematics 2016-05-05 Gwenaël Joret , Piotr Micek , William T. Trotter , Ruidong Wang , Veit Wiechert

Planar posets can have arbitrarily large dimension. However, a planar poset of height $h$ has dimension at most $192h+96$, while a planar poset with $t$ minimal elements has dimension at most $2t+1$. In particular, a planar poset with a…

The Dushnik-Miller dimension of a partially-ordered set $P$ is the smallest $d$ such that one can embed $P$ into a product of $d$ linear orders. We prove that the dimension of the divisibility order on the interval $\{1, \dotsc, n\}$, is…

Combinatorics · Mathematics 2021-01-18 David Lewis , Victor Souza

The interval poset of a permutation is the set of intervals of a permutation, ordered with respect to inclusion. It has been introduced and studied recently in [B. Tenner, arXiv:2007.06142]. We study this poset from the perspective of the…

Combinatorics · Mathematics 2024-06-11 Mathilde Bouvel , Lapo Cioni , Benjamin Izart

The dimension of a partially-ordered set (poset), introduced by Dushnik and Miller (1941), has been studied extensively in the literature. Recently, Ueckerdt (2016) proposed a variation called local dimension which makes use of partial…

In a recent study by Tenner, the concept of the interval poset of a permutation was introduced to effectively represent all intervals and their inclusions within a permutation. In this paper, we present a new geometric viewpoint on interval…

Combinatorics · Mathematics 2025-09-30 Eli Bagno , Estrella Eisenberg , Shulamit Reches , Moriha Sigron

We show that height $h$ posets that have planar cover graphs have dimension $\mathcal{O}(h^6)$. Previously, the best upper bound was $2^{\mathcal{O}(h^3)}$. Planarity plays a key role in our arguments, since there are posets such that (1)…

Combinatorics · Mathematics 2022-10-13 Jakub Kozik , Piotr Micek , William T. Trotter
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