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On the adaptive wavelet estimation of a multidimensional regression function under α -mixing dependence: Beyond the standard assumptions on the noise

Christophe Chesneau (2013)

Commentationes Mathematicae Universitatis Carolinae

We investigate the estimation of a multidimensional regression function f from n observations of an α -mixing process ( Y , X ) , where Y = f ( X ) + ξ , X represents the design and ξ the noise. We concentrate on wavelet methods. In most papers considering this problem, either the proposed wavelet estimator is not adaptive (i.e., it depends on the knowledge of the smoothness of f in its construction) or it is supposed that ξ is bounded or/and has a known distribution. In this paper, we go far beyond this classical framework....

On the amount of information resulting from empirical and theoretical knowledge.

Igor Vajda, Arnost Vesely, Jana Zvarova (2005)

Revista Matemática Complutense

We present a mathematical model allowing formally define the concepts of empirical and theoretical knowledge. The model consists of a finite set P of predicates and a probability space (Ω, S, P) over a finite set Ω called ontology which consists of objects ω for which the predicates π ∈ P are either valid (π(ω) = 1) or not valid (π(ω) = 0). Since this is a first step in this area, our approach is as simple as possible, but still nontrivial, as it is demonstrated by examples. More realistic approach...

On the analogy between self-gravitating Brownian particles and bacterial populations

Pierre-Henri Chavanis, Magali Ribot, Carole Rosier, Clément Sire (2004)

Banach Center Publications

We develop the analogy between self-gravitating Brownian particles and bacterial populations. In the high friction limit, the self-gravitating Brownian gas is described by the Smoluchowski-Poisson system. These equations can develop a self-similar collapse leading to a finite time singularity. Coincidentally, the Smoluchowski-Poisson system corresponds to a simplified version of the Keller-Segel model of bacterial populations. In this biological context, it describes the chemotactic aggregation...

On the Argmin-sets of stochastic processes and their distributional convergence in Fell-type-topologies

Dietmar Ferger (2011)

Kybernetika

Let ϵ - ( Z ) be the collection of all ϵ -optimal solutions for a stochastic process Z with locally bounded trajectories defined on a topological space. For sequences ( Z n ) of such stochastic processes and ( ϵ n ) of nonnegative random variables we give sufficient conditions for the (closed) random sets ϵ n - ( Z n ) to converge in distribution with respect to the Fell-topology and to the coarser Missing-topology.

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