All a b c d e f g h i j k l m n o p q r s t u v w x y z Other

Previous Page 27 Next

Displaying 521 – 540 of 838

Showing per page

On the estimation of the autocorrelation function

Manuel Duarte Ortigueira (2010)

Discussiones Mathematicae Probability and Statistics

The autocorrelation function has a very important role in several application areas involving stochastic processes. In fact, it assumes the theoretical base for Spectral analysis, ARMA (and generalizations) modeling, detection, etc. However and as it is well known, the results obtained with the more current estimates of the autocorrelation function (biased or not) are frequently bad, even when we have access to a large number of points. On the other hand, in some applications, we need to perform...

On the estimation of the drift coefficient in diffusion processes with random stopping times.

Ramón Gutiérrez Jáimez, Aurora Hermoso Carazo, Manuel Molina Fernández (1986)

Trabajos de Estadística

This paper considers stochastic differential equations with solutions which are multidimensional diffusion processes with drift coefficient depending on a parametric vector θ. By considering a trajectory observed up to a stopping time, the maximum likelihood estimator for θ has been obtained and its consistency and asymptotic normality have been proved.

On the extremal behavior of a Pareto process: an alternative for ARMAX modeling

Marta Ferreira (2012)

Kybernetika

In what concerns extreme values modeling, heavy tailed autoregressive processes defined with the minimum or maximum operator have proved to be good alternatives to classical linear ARMA with heavy tailed marginals (Davis and Resnick [8], Ferreira and Canto e Castro [13]). In this paper we present a complete characterization of the tail behavior of the autoregressive Pareto process known as Yeh-Arnold-Robertson Pareto(III) (Yeh et al. [32]). We shall see that it is quite similar to the first order...

On the law of large numbers for continuous-time martingales and applications to statistics.

Hung T. Nguyen, Tuan D. Pham (1982)

Stochastica

In order to develop a general criterion for proving strong consistency of estimators in Statistics of stochastic processes, we study an extension, to the continuous-time case, of the strong law of large numbers for discrete time square integrable martingales (e.g. Neveu, 1965, 1972). Applications to estimation in diffusion models are given.

On the suitability of the internet multimedia storage for steganographic information transfer in MP4 files

Matúš Jókay, Ján Baroš (2012)

Kybernetika

The aim of this work is to analyze suitability of existing internet multimedia storage services to use as a covert (steganographic) transmission channel. After general overview we focus specifically on the YouTube service. In particular, we study the feasibility of the recently proposed new steganographic technique [6] of hiding information directly in the structure of the mp4-encoded video file. Our statistical analysis of the set of 1000 video files stored by this service show the practical limitations...

On unequally spaced AR(1) process

Jan Šindelář, Jiří Knížek (2003)

Kybernetika

Discrete autoregressive process of the first order is considered. The process is observed at unequally spaced time instants. Both least squares estimate and maximum likelihood estimate of the autocorrelation coefficient are analyzed. We show some dangers related with the estimates when the true value of the autocorrelation coefficient is small. Monte-Carlo method is used to illustrate the problems.

Currently displaying 521 – 540 of 838