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Periodic moving average process

Tomáš Cipra (1985)

Aplikace matematiky

Periodic moving average processes are representatives of the class of periodic models suitable for the description of some seasonal time series and for the construction of multivariate moving average models. The attention having been lately concentrated mainly on periodic autoregressions, some methods of statistical analysis of the periodic moving average processes are suggested in the paper. These methods include the estimation procedure (based on Durbin's construction of the parameter estimators...

Permanents, order statistics, outliers, and robustness.

Narayanaswamy Balakrishnan (2007)

Revista Matemática Complutense

In this paper, we consider order statistics and outlier models, and focus primarily on multiple-outlier models and associated robustness issues. We first synthesise recent developments on order statistics arising from independent and non-identically distributed random variables based primarily on the theory of permanents. We then highlight various applications of these results in evaluating the robustness properties of several linear estimators when multiple outliers are possibly present in the...

Permutation tests for multiple changes

Marie Hušková, Aleš Slabý (2001)

Kybernetika

Approximations to the critical values for tests for multiple changes in location models are obtained through permutation tests principle. Theoretical results say that the approximations based on the limit distribution and the permutation distribution of the test statistics behave in the same way in the limit. However, the results of simulation study show that the permutation tests behave considerably better than the corresponding tests based on the asymptotic critical value.

Piecewise approximation and neural networks

Martina Révayová, Csaba Török (2007)

Kybernetika

The paper deals with the recently proposed autotracking piecewise cubic approximation (APCA) based on the discrete projective transformation, and neural networks (NN). The suggested new approach facilitates the analysis of data with complex dependence and relatively small errors. We introduce a new representation of polynomials that can provide different local approximation models. We demonstrate how APCA can be applied to especially noisy data thanks to NN and local estimations. On the other hand,...

P-insesgadez asintótica y robustez en la estimación lineal con modelos de superpoblaciones: un criterio de selección.

José Miguel Casas Sánchez, Marta Guijarro Garvi (1994)

Qüestiió

Se analiza la estimación lineal de la media poblacional desde el punto de vista de los modelos de superpoblaciones con parámetros desconocidos y correlación no nula. La posible existencia de errores de especificación en el modelo determina el estudio de propiedades tales como la insesgadez asintótica respecto al diseño de muestreo y la robustez débil, deseables para asegurar la robustez de los estimadores frente a este tipo de errores. Se establece, así, un criterio de selección entre estimadores...

Pirámides indexadas y disimilaridades piramidales.

Carles Capdevila Marquès, Antoni Arcas Pons (1995)

Qüestiió

En este trabajo se pretende una formalización de las bases matemáticas sobre las que se amparan los modelos de clasificación y representación piramidal, estableciéndose para ello una relación entre los conceptos de pirámide indexada y disimilaridad piramidal. Asimismo se precisa el concepto de información redundante, contenida en una estructura piramidal, y se dan criterios objetivos para poder prescindir de ella sin que ello suponga una modificación de la estructura piramidal.

Pivotal inference and the Bayesian controversy.

George A. Barnard (1980)

Trabajos de Estadística e Investigación Operativa

The theory of pivotal inference applies when parameters are defined by reference to their effect on observations rather than their effect on distributions. It is shown that pivotal inference embraces both Bayesian and frequentist reasoning.

Plan de muestreo secuencial basado en la energía informacional para una población exponencial.

Leandro Pardo, Domingo Morales, Vicente Quesada (1985)

Trabajos de Estadística e Investigación Operativa

En Pardo (1984), se propuso un Plan de Muestreo Secuencial basado en la Energía Informacional (P.M.S.E.I.), análogo al propuesto por Lindley (1956, 1957) a partir de la Entropía de Shannon, con el fin de recoger información acerca de un parámetro desconocido θ. En esta comunicación se aplica el P.M.S.E.I. al caso concreto de la recogida de información acerca del parámetro θ de una distribución exponencial y se extiende el concepto de P.M.S.E.I. al caso en que el estadístico esté interesado en recoger...

Planar anisotropy revisited

Viktor Beneš, Arun M. Gokhale (2000)

Kybernetika

The paper concerns estimation of anisotropy of planar fibre systems using the relation between the rose of directions and the rose of intersections. The discussion about the properties of the Steiner compact estimator is based on both theoretical and simulation results. The approach based on the distribution of the Prokhorov distance between the estimated and true rose of directions is developed. Finally the curved test systems are investigated in both Fourier and Steiner compact analysis of anisotropy....

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