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作者：Caravenna, Francesco; Giacomin, Giambattista; Zambotti, Lorenzo
作者单位：University of Padua; Universite Paris Cite; Universite Paris Cite; Sorbonne Universite; Centre National de la Recherche Scientifique (CNRS); CNRS - National Institute for Mathematical Sciences (INSMI); Universite Paris Cite; Centre National de la Recherche Scientifique (CNRS); CNRS - National Institute for Mathematical Sciences (INSMI); Sorbonne Universite; Sorbonne Universite
摘要：We consider a general model of a heterogeneous polymer chain fluctuating in the proximity of an interface between two selective solvents. The heterogeneous character of the model comes from the fact that the monomer units interact with the solvents and with the interface according to some charges that they carry. The charges repeat themselves along the chain in a periodic fashion. The main question concerning this model is whether the polymer remains tightly close to the interface, a phenomeno...
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作者：Hachem, Walid; Loubaton, Philippe; Najim, Jamal
作者单位：Universite Paris Saclay; Centre National de la Recherche Scientifique (CNRS); CNRS - Institute for Information Sciences & Technologies (INS2I); Universite Gustave-Eiffel; ESIEE Paris; Institut Polytechnique de Paris; Ecole Nationale des Ponts et Chaussees; Centre National de la Recherche Scientifique (CNRS); IMT - Institut Mines-Telecom; Institut Polytechnique de Paris; Telecom Paris
摘要：Consider an N x n random matrix Y-n = (Y-ij(n)) where the entries are given by Y-ij(n) = sigma(ij)(n)/root n X-ij(n) the X-ij(n) being independent and identically distributed centered with unit variance and satisfying some mild moment assumption. Consider now a deterministic N x n matrix A(n) whose columns and rows are uniformly bounded in the Euclidean norm. Let Sigma(n) = Y-n + A(n). We prove in this article that there exists a deterministic N x N matrix-valued function T-n(z) analytic in C ...
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作者：Yu, Feng
作者单位：University of Oxford
摘要：This paper deals with a model of sympatric speciation, that is, speciation in the absence of geographical separation, originally proposed by U. Dieckmarm and M. Doebeli in 1999. We modify their original model to obtain a Fleming-Viot type model and study its stationary distribution. We show that speciation may occur, that is, the stationary distribution puts most of the mass on a configuration that does not concentrate on the phenotype with maximum carrying capacity, if competition between phe...
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作者：Blath, Jochen; Etheridge, Alison; Meredith, Mark
作者单位：Technical University of Berlin; University of Oxford
摘要：We propose two models of the evolution of a pair of competing populations. Both are lattice based. The first is a compromise between fully spatial models, which do not appear amenable to analytic results, and interacting particle system models, which do not, at present, incorporate all of the competitive strategies that a population might adopt. The second is a simplification of the first, in which competition is only supposed to act within lattice sites and the total population size within ea...
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作者：Yu, Feng
作者单位：University of Oxford
摘要：We study dioccious (i.e., two-sex) branching particle system models, where there are two types of particles, modeling the male and female populations, and where birth of new particles requires the presence of both male and female particles. We show that stationary distributions of various dioecious branching particle models are nontrivial under certain conditions, for example, when there is sufficiently fast stirring.
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作者：Roellin, Adrian
作者单位：University of Zurich
摘要：It is shown that the method of exchangeable pairs introduced by Stein [Approximate Computation of Expectations (1986) IMS, Hayward, CA] for normal approximation can effectively be used for translated Poisson approximation. Introducing an additional smoothness condition, one can obtain approximation results in total variation and also in a local limit metric. The result is applied, in particular, to the anti-voter model on finite graphs as analyzed by Rinott and Rotar [Ann. Appl. Probab. 7 (199...
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作者：Champagnat, Nicolas; Lambert, Amaury
作者单位：Leibniz Association; Weierstrass Institute for Applied Analysis & Stochastics; Sorbonne Universite; Universite PSL; Ecole Normale Superieure (ENS); Sorbonne Universite
摘要：The biological theory of adaptive dynamics proposes a description of the long-term evolution of a structured asexual population. It is based on the assumptions of large population, rare mutations and small mutation steps, that lead to a deterministic ODE describing the evolution of the dominant type, called the canonical equation of adaptive dynamics. Here, in order to include the effect of stochasticity (genetic drift), we consider self-regulated randomly fluctuating populations subject to mu...
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作者：Deijfen, Maria; Haggstrom, Olle
作者单位：Stockholm University; Chalmers University of Technology
摘要：The two-type Richardson model describes the growth of two competing infections on Z(d) and the main question is whether both infection types can simultaneously grow to occupy infinite parts of Z(d). For bounded initial configurations, this has been thoroughly studied. In this paper, an unbounded initial configuration consisting of points x = (x(1),center dot center dot center dot, x(d)) in the hyperplane H = {X epsilon Z(d) : x(1) = 0} is considered. It is shown that, starting from a configura...
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作者：Bhatnagar, Nayantara; Caputo, Pietro; Tetali, Prasad; Vigoda, Eric
作者单位：University System of Georgia; Georgia Institute of Technology; Sapienza University Rome; University System of Georgia; Georgia Institute of Technology; University System of Georgia; Georgia Institute of Technology
摘要：We study Markov chains which model genome rearrangements. These models are useful for studying the equilibrium distribution of chromosomal lengths, and are used in methods for estimating genomic distances. The primary Markov chain studied in this paper is the top-swap Markov chain. The top-swap chain is a card-shuffling process with n cards divided over k decks, where the cards are ordered within each deck. A transition consists of choosing a random pair of cards, and if the cards lie in diffe...
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作者：Elie, Romuald; Fermanian, Jean-David; Touzi, Nizar
作者单位：Institut Polytechnique de Paris; ENSAE Paris; BNP Paribas; Centre National de la Recherche Scientifique (CNRS); CNRS - National Institute for Mathematical Sciences (INSMI); Institut Polytechnique de Paris; Ecole Polytechnique
摘要：Greek weight associated to a parameterized random variable Z(lambda) is a random variable pi such that del lambda E[phi(Z(lambda))] = E[phi(Z(lambda))pi] for any function phi. The importance of the set of Greek weights for the purpose of Monte Carlo simulations has been highlighted in the recent literature. Our main concern in this paper is to devise methods which produce the optimal weight, which is well known to be given by the score, in a general context where the density of Z(lambda) is no...
