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Related papers: Upper cluster algebras and choice of ground ring

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Some key issues in robust clustering are discussed with focus on Gaussian mixture model based clustering, namely the formal definition of outliers, ambiguity between groups of outliers and clusters, the interaction between robust clustering…

Machine Learning · Statistics 2023-08-29 Christian Hennig

We study the duality between the mutations and the initial-seed mutations in cluster algebras, where the initial-seed mutations are the transformations of rational expressions of cluster variables in terms of the initial cluster under the…

Rings and Algebras · Mathematics 2019-05-16 Shogo Fujiwara , Yasuaki Gyoda

Considered as commutative algebras, cluster algebras can be very unpleasant objects. However, the first author introduced a condition known as "local acyclicity" which implies that cluster algebras behave reasonably. One of the earliest and…

Combinatorics · Mathematics 2015-06-23 Greg Muller , David E. Speyer

This paper investigates the Poisson geometry associated to a cluster algebra over the complex numbers, and its relationship to compatible torus actions. We show, under some assumptions, that each Noetherian cluster algebra has only finitely…

Representation Theory · Mathematics 2012-03-01 Sebastian Zwicknagl

Non-singular weighted surface algebras satisfy the necessary condition found in [6] for existence of cluster tilting modules. We show that any such algebra whose Gabriel quiver is bipartite, has a module satisfying the necessary ext…

Representation Theory · Mathematics 2021-01-28 Karin Erdmann

We give a presentation of a finite crystallographic reflection group in terms of an arbitrary seed in the corresponding cluster algebra of finite type and interpret the presentation in terms of companion bases in the associated root system.

Group Theory · Mathematics 2020-12-21 Michael Barot , Bethany Marsh

Many systems of interest in cryptography consist of equations of the same degree. Under the assumption that the degree of regularity is finite, we prove upper bounds on the degree of regularity of a system of equations of the same degree,…

Cryptography and Security · Computer Science 2026-02-02 Giulia Gaggero , Elisa Gorla

Spectral clustering is a powerful method for finding structure in a dataset through the eigenvectors of a similarity matrix. It often outperforms traditional clustering algorithms such as $k$-means when the structure of the individual…

Numerical Analysis · Mathematics 2019-04-26 Paola Favati , Grazia Lotti , Ornella Menchi , Francesco Romani

We study the relationship between $n$-cluster tilting modules over $n$ representation finite algebras and the Euler forms. We show that the dimension vectors of cluster-indecomposable modules give the roots of the Euler form. Moreover, we…

Representation Theory · Mathematics 2014-02-26 Yuya Mizuno

In this paper, we show that the tilting modules over a cluster-tilted algebra $A$ lift to tilting objects in the associated cluster category $\mathcal{C}_H$. As a first application, we describe the induced exchange relation for tilting…

Representation Theory · Mathematics 2007-10-25 David Smith

Consistency is a key property of all statistical procedures analyzing randomly sampled data. Surprisingly, despite decades of work, little is known about consistency of most clustering algorithms. In this paper we investigate consistency of…

Statistics Theory · Mathematics 2008-12-18 Ulrike von Luxburg , Mikhail Belkin , Olivier Bousquet

We study the homogeneous coordinate rings of partial flag varieties and Grassmannians in their Pl\"ucker embeddings and exhibit an embedding of the former into the latter. Both rings are cluster algebras and the embedding respects the…

Algebraic Geometry · Mathematics 2025-04-29 Lara Bossinger , Jian-Rong Li

We show that the quantum coordinate ring of the unipotent subgroup N(w) of a symmetric Kac-Moody group G associated with a Weyl group element w has the structure of a quantum cluster algebra. This quantum cluster structure arises naturally…

Quantum Algebra · Mathematics 2013-04-29 C. Geiss , B. Leclerc , J. Schröer

The explosion in the amount of data available for analysis often necessitates a transition from batch to incremental clustering methods, which process one element at a time and typically store only a small subset of the data. In this paper,…

Machine Learning · Computer Science 2014-06-26 Margareta Ackerman , Sanjoy Dasgupta

In cluster analysis, it can be useful to interpret the partition built from the data in the light of external categorical variables which were not directly involved to cluster the data. An approach is proposed in the model-based clustering…

A key issue in cluster analysis is the choice of an appropriate clustering method and the determination of the best number of clusters. Different clusterings are optimal on the same data set according to different criteria, and the choice…

Methodology · Statistics 2020-06-24 Serhat Emre Akhanli , Christian Hennig

We introduce ordered and unordered configuration spaces of 'clusters' of points in an Euclidean space $\mathbb{R}^d$, where points in each cluster satisfy a 'verticality' condition, depending on a decomposition $d=p+q$. We compute the…

Algebraic Topology · Mathematics 2022-05-03 Andrea Bianchi , Florian Kranhold

Plabic graphs are intimately connected to the positroid stratification of the positive Grassmannian. The duals to these graphs are quivers, and it is possible to associate to them cluster algebras. For the top-cell graph of $Gr_{+}(k,n)$,…

High Energy Physics - Theory · Physics 2015-06-22 Miguel F. Paulos , Burkhard U. W. Schwab

We give a combinatorial intepretation of cluster variables of a specific cluster algebra under a mutation sequence of period 6, in terms of perfect matchings of subgraphs of the brane tiling dual to the quiver associated with the cluster…

Combinatorics · Mathematics 2015-11-20 Sicong Zhang

This paper presents and analyzes an approach to cluster-based inference for dependent data. The primary setting considered here is with spatially indexed data in which the dependence structure of observed random variables is characterized…

Statistics Theory · Mathematics 2022-11-16 Jianfei Cao , Christian Hansen , Damian Kozbur , Lucciano Villacorta
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