Application domains for the Delta method

The Delta method uses truncated Lagrange expansions of statistics to obtain approximations to their distributions. In this paper, we consider statistics Y=g(μ+X), where X is any random vector. We obtain domains 𝒟 such that, when μ∈𝒟, we may apply the distribution derived from the Delta method. Namely, we will consider an application on the normal case to illustrate our approach.     

Chisquared and related inducing pivot variables: an application to orthogonal mixed models

Abstract

We use chi-squared and related pivot variables to induce probability measures for model parameters, obtaining some results that will be useful on the induced densities. As illustration we considered mixed models with balanced cross nesting and used the algebraic structure to derive confidence intervals for the variance components. A numerical application is presented.     

Sensitivity analysis in multivariate methods: Decomposition of an arbitrary influence into a finite number of components

The influence function of the covariance matrix is decomposed into a finite number of components. This decomposition provides a useful tool to develop efficient methods for computing empirical influence curves related to various multivariate methods. It can also be used to characterize multivariate methods from the sensitivity perspective. A numerical example is given to demonstrate efficient computing and to characterize some procedures of exploratory factor analysis.     

Nonparametric estimation of the hazard function under dependence conditions

The estimation of the hazard rate has a great number of practical appli¬cations in dependence situations (seismicity analysis, reliability, economics), Based on kernel estimates of the density and the distribution function, we study the properties of the nonparametric estimator of the hazard function as-sociated with a strongly mixing time series. We prove consistency and asymp¬totic normality properties, and a cross-validation method for the smoothing parameter selection is studied. Some simulations and a practical application to real data are also shown.     

The Estimation and Testing of the Cointegration Order Based on the Frequency Domain

ABSTRACT

This article proposes a method to estimate the degree of cointegration in bivariate series and suggests a test statistic for testing noncointegration based on the determinant of the spectral density matrix for the frequencies close to zero. In the study, series are assumed to be I(d), 0 < d ? 1, with parameter d supposed to be known. In this context, the order of integration of the error series is I(d ? b), b ∈ [0, d]. Besides, the determinant of the spectral density matrix for the dth difference series is a power function of b. The proposed estimator for b is obtained here performing a regression of logged determinant on a set of logged Fourier frequencies. Under the null hypothesis of noncointegration, the expressions for the bias and variance of the estimator were derived and its consistency property was also obtained. The asymptotic normality of the estimator, under Gaussian and non-Gaussian innovations, was also established. A Monte Carlo study was performed and showed that the suggested test possesses correct size and good power for moderate sample sizes, when compared with other proposals in the literature. An advantage of the method proposed here, over the standard methods, is that it allows to know the order of integration of the error series without estimating a regression equation. An application was conducted to exemplify the method in a real context.     

SNA关于雇员股票期权核算方法的研究及其对中国国民经济核算的影响

本文首先综述了雇员股票期权的定义以及国际企业会计准则对雇员股票期权的处理方法.接着介绍了2008年SNA关于雇员股票期权的处理方法,并通过雇员股票期权账户登录表,更直观地展示了雇员股票期权在授权日、含权日和行权日之间,如何分别在雇主账户与雇员账户中记录.最后,对部分国家的经验数据进行了分析,并探讨了雇员股票期权作为雇员报酬处理对于中国国民经济核算,特别是收入分配核算的影响.     

The generalized inverse Weibull distribution

The inverse Weibull distribution has the ability to model failure rates which are quite common in reliability and biological studies. A three-parameter generalized inverse Weibull distribution with decreasing and unimodal failure rate is introduced and studied. We provide a comprehensive treatment of the mathematical properties of the new distribution including expressions for the moment generating function and the rth generalized moment. The mixture model of two generalized inverse Weibull distributions is investigated. The identifiability property of the mixture model is demonstrated. For the first time, we propose a location-scale regression model based on the log-generalized inverse Weibull distribution for modeling lifetime data. In addition, we develop some diagnostic tools for sensitivity analysis. Two applications of real data are given to illustrate the potentiality of the proposed regression model.     

Back to the South: Social and Political Aspects of Latin American Migration to Southern Europe

When migration from the Latin American and Caribbean countries to Europe is studied, a preferential stream can be noted towards southern Europe. There would also appear to have been a remarkable growth in the volume of flows in this direction in recent years. The flows themselves vary: in the case of Spain, nationals from Ecuador, Colombia, Peru and Argentina predominate; Portugal is the recipient of Brazilians; and Italy mainly plays host to nationals from Peru and Ecuador. These flows reveal the importance of various factors: economic push and pull mechanisms; the former presence in the region of Spain and Portugal as erstwhile colonial powers; the earlier waves of emigrants in that direction from Spain, Portugal and Italy; a relatively more favourable social reception; and political initiatives that favour the new sending countries. In other words, economic gaps, former historical links, cultural and linguistic affinities, family ties and diplomatic channels suggest that a special route exists for migrants from Latin America. The topics that will be expanded upon in this paper include the factors explaining recent immigration to southern Europe; the economic incorporation of immigrants; the social framework of flows, including reactions from local populations; and the tentative and multiple policy responses to immigration. Conclusions indicate that the potential for movements from Latin America, resulting from both previous and current links, has proved to be a favourable response to the need for immigrant workers in the case of southern European societies. Despite the familiar path (albeit in the reverse direction), the economic incorporation of immigrants has mainly occurred in the low‐ranking jobs, as was the case with other inflows. This stemmed from market needs, state failures and the importance of the family. However, given the numerous links between Latin America and southern Europe, the social and policy responses adopted towards these immigrants seem to have been more beneficial than towards other groups.