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On factorization of probability distributions over directed graphs

František Matúš, Bernhard Strohmeier (1998)

Kybernetika

Four notions of factorizability over arbitrary directed graphs are examined. For acyclic graphs they coincide and are identical with the usual factorization of probability distributions in Markov models. Relations between the factorizations over circuits are described in detail including nontrivial counterexamples. Restrictions on the cardinality of state spaces cause that a factorizability with respect to some special cyclic graphs implies the factorizability with respect to their, more simple,...

On families of weakly dependent random variables

Tomasz Łuczak (2011)

Banach Center Publications

Let ( k ) be a family of random independent k-element subsets of [n] = 1,2,...,n and let ( ( k ) , ) = ( k ) ( ) denote a family of ℓ-element subsets of [n] such that the event that S belongs to ( k ) ( ) depends only on the edges of ( k ) contained in S. Then, the edges of ( k ) ( ) are ’weakly dependent’, say, the events that two given subsets S and T are in ( k ) ( ) are independent for vast majority of pairs S and T. In the paper we present some results on the structure of weakly dependent families of subsets obtained in this way. We also list...

On fine properties of mixtures with respect to concentration of measure and Sobolev type inequalities

Djalil Chafaï, Florent Malrieu (2010)

Annales de l'I.H.P. Probabilités et statistiques

Mixtures are convex combinations of laws. Despite this simple definition, a mixture can be far more subtle than its mixed components. For instance, mixing gaussian laws may produce a potential with multiple deep wells. We study in the present work fine properties of mixtures with respect to concentration of measure and Sobolev type functional inequalities. We provide sharp Laplace bounds for Lipschitz functions in the case of generic mixtures, involving a transportation cost diameter of the mixed...

On finite rank deformations of Wigner matrices

Alessandro Pizzo, David Renfrew, Alexander Soshnikov (2013)

Annales de l'I.H.P. Probabilités et statistiques

We study the distribution of the outliers in the spectrum of finite rank deformations of Wigner random matrices under the assumption that the absolute values of the off-diagonal matrix entries have uniformly bounded fifth moment and the absolute values of the diagonal entries have uniformly bounded third moment. Using our recent results on the fluctuation of resolvent entries (On fluctuations of matrix entries of regular functions of Wigner matrices with non-identically distributed entries, Unpublished...

On formulae for central moments of counting distributions

Katarzyna Steliga, Dominik Szynal (2015)

Applicationes Mathematicae

The aim of this article is to give new formulae for central moments of the binomial, negative binomial, Poisson and logarithmic distributions. We show that they can also be derived from the known recurrence formulae for those moments. Central moments for distributions of the Panjer class are also studied. We expect our formulae to be useful in many applications.

On fully coupled continuous time random walks

W. Szczotka, P. Żebrowski (2012)

Applicationes Mathematicae

Continuous time random walks with jump sizes equal to the corresponding waiting times for jumps are considered. Sufficient conditions for the weak convergence of such processes are established and the limiting processes are identified. Furthermore one-dimensional distributions of the limiting processes are given under an additional assumption.

On functional measures of skewness

Renata Dziubińska, Dominik Szynal (1996)

Applicationes Mathematicae

We introduce a concept of functional measures of skewness which can be used in a wider context than some classical measures of asymmetry. The Hotelling and Solomons theorem is generalized.

Currently displaying 301 – 320 of 1206