We consider classes of multivariate distributions which can model skewness and are closed under orthogonal transformations. We review two classes of such distributions proposed in the literature and focus our attention on a particular, yet quite flexible, subclass of one of these classes....

Aquí se explica el funcionamiento de los enlaces con TRAMO/SEATS y X12ARIMA de Gretl. Se describe su forma de utilización y la equivalencia entre las entradas de menú de Gretl y los parámetros en línea de instrucciones de TRAMO/SEATS.

The outline of a proposed new unbalanced bidding model is discussed. Background is provided as regards the role of item price loading, otherwise known as unbalanced bidding. Three types of loading are described, namely those of ‘front-end loading’, ‘back-end loading’ and ‘quantity...

Heisenberg's principle of indeterminacy is applied to stationary time series models. The position and velocity of a forecast are defined and are shown to be imperfectly correlated. Then a first-order autoregression is used to illustrate the trade-off between precision of position and precision...

The opening of the residential UK electricity sector in 1999 motivated several studies of its impact on both the level and structure of retail charges, and on incumbents’ market power. Using regional observations on tariffs offered in January 2004, the present paper supports previous results...

The motivation behind the influence analysis is to increase the adequacy of the fitted model. Several local influence diagnostics have been proposed for different models such as linear regression, generalized linear, Weibull regression, proportional hazards etc. models by different authors on...

Classical regression analysis uses partial coefficients to measure the influences of some variables (regressors) on another variable (regressand). However, a descriptive point of view shows that these coefficients are very bad measures of influence. Their interpretation as an average change of...

This document introduce the obtained results of the econometric estimation of cement demand and supply in Bolivia considered as a simultaneous equations model, based on two equations, one for the demand and another for the supply. The objective of this study is to quantify the forces that affect...

We establish a maximal moment inequality for the weighted sum of a long- range dependent process. An extension to H$\acute{a}$jek-R$\acute{e}$ny and Chow's type inequality is then obtained. It enables us to deduce a strong law for the weighted sum of a stationary long-range dependent time...