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In this paper we consider an aggregation model f: X1 x ... x Xn --> Y for arbitrary sets X1, ..., Xn and a finite distributive lattice Y, factorizable as f(x1, ..., xn) = p(u1(x1), ..., un(xn)), where p is an n-variable lattice polynomial…

Rings and Algebras · Mathematics 2011-10-11 Miguel Couceiro , Tamás Waldhauser

We discuss the following extremal problem and its relevance to the sum of the so-called superoptimal singular values of a matrix function: Given an $m\times n$ matrix function $\Phi$ on the unit circle $\mathbb{T}$, when is there a matrix…

Functional Analysis · Mathematics 2009-09-09 Alberto A. Condori

We consider matrix functions with certain invariance under inversion in the unit circle. If such a function satisfies a positivity assumption on the unit circle, then only zero partial indices appear in its Riemann-Hilbert (Wiener-Hopf)…

Mathematical Physics · Physics 2018-06-01 Hideshi Yamane

The development of randomized algorithms for numerical linear algebra, e.g. for computing approximate QR and SVD factorizations, has recently become an intense area of research. This paper studies one of the most frequently discussed…

Numerical Analysis · Computer Science 2013-08-28 Rafi Witten , Emmanuel Candes

We introduce categories of weak factorization algebras and factorization spaces, and prove that they are equivalent to the categories of ordinary factorization algebras and spaces, respectively. This allows us to define the pullback of a…

Algebraic Geometry · Mathematics 2019-11-06 Emily Cliff

This is a study of inner-outer factorization for analytic matrix-valued functions focusing on representations of the factors in terms of multiplicative integrals. Included is a brief introduction to the theory of multiplicative integrals…

Complex Variables · Mathematics 2024-12-18 Joris Roos

We start with elementary algebraic theory of factorization of linear ordinary differential equations developed in the period 1880-1930. After exposing these classical results we sketch more sophisticated algorithmic approaches developed in…

Symbolic Computation · Computer Science 2008-01-10 S. P. Tsarev

We study the non-uniqueness of factorizations of non zero-divisors into atoms (irreducibles) in noncommutative rings. To do so, we extend concepts from the commutative theory of non-unique factorizations to a noncommutative setting. Several…

Rings and Algebras · Mathematics 2015-09-03 Nicholas R. Baeth , Daniel Smertnig

This is the second one in a series of papers classifying the factorizations of almost simple groups with nonsolvable factors. In this paper we deal with almost simple unitary groups.

Group Theory · Mathematics 2021-08-03 Cai Heng Li , Lei Wang , Binzhou Xia

We develop a new collaborative filtering (CF) method that combines both previously known users' preferences, i.e. standard CF, as well as product/user attributes, i.e. classical function approximation, to predict a given user's interest in…

Machine Learning · Computer Science 2007-05-23 Jacob Abernethy , Francis Bach , Theodoros Evgeniou , Jean-Philippe Vert

If K/k is a function field in one variable of positive characteristic, we describe a general algorithm to factor one-variable polynomials with coefficients in K. The algorithm is flexible enough to find factors subject to additional…

Number Theory · Mathematics 2024-09-16 Jose Felipe Voloch

A common approach for describing classes of functions and probability measures on a topological space $\mathcal{X}$ is to construct a suitable map $\Phi$ from $\mathcal{X}$ into a vector space, where linear methods can be applied to address…

Functional Analysis · Mathematics 2022-02-02 Chad Giusti , Darrick Lee , Vidit Nanda , Harald Oberhauser

Let $A$ be a Banach algebra with a bounded left approximate identity $\{e_\lambda\}_{\lambda\in\Lambda}$, let $\pi$ be a continuous representation of $A$ on a Banach space $X$, and let $S$ be a non-empty subset of $X$ such that…

Functional Analysis · Mathematics 2017-05-30 Marcel de Jeu , Xingni Jiang

In the past decade, matrix factorization has been extensively researched and has become one of the most popular techniques for personalized recommendations. Nevertheless, the dot product adopted in matrix factorization based recommender…

Information Retrieval · Computer Science 2018-06-05 Shuai Zhang , Lina Yao , Yi Tay , Xiwei Xu , Xiang Zhang , Liming Zhu

Factor graphs are important models for succinctly representing probability distributions in machine learning, coding theory, and statistical physics. Several computational problems, such as computing marginals and partition functions, arise…

Machine Learning · Computer Science 2017-08-09 Damian Straszak , Nisheeth K. Vishnoi

In this paper we prove a few propositions concerning factorizations of morphisms in pro categories, the most important of which solves an open problem of Isaksen concerning the existence of certain types of functorial factorizations. On our…

Category Theory · Mathematics 2013-05-21 Ilan Barnea , Tomer M. Schlank

A simple criterion for a functor to be finitary is presented: we call $F$ finitely bounded if for all objects $X$ every finitely generated subobject of $FX$ factorizes through the $F$-image of a finitely generated subobject of $X$. This is…

Category Theory · Mathematics 2019-10-22 Jiří Adámek , Stefan Milius , Lurdes Sousa , Thorsten Wißmann

This paper proves some results concerning the polar factorisation of an integrable vector-valued function u into the composition of the gradient of a convex function with a measure-preserving mapping. Not every integrable function has a…

Functional Analysis · Mathematics 2007-12-14 R. J. Douglas

We establish a complete algebraic characterization of self-similar iterated function systems $\Phi$ on $\mathbb{R}^{d}$, for which there exists a positive probability vector $p$ so that the Fourier transform of the self-similar measure…

Dynamical Systems · Mathematics 2021-04-22 Ariel Rapaport

Functions of one or more variables are usually approximated with a basis: a complete, linearly-independent system of functions that spans a suitable function space. The topic of this paper is the numerical approximation of functions using…

Numerical Analysis · Mathematics 2018-11-07 Ben Adcock , Daan Huybrechs