Asymptotic Skewness in Exponential Family Nonlinear Models

In this article, we give an asymptotic formula of order n ^?1/2, where n is the sample size, for the skewness of the distributions of the maximum likelihood estimates of the pa-ra-meters in exponencial family nonlinear models. We generalize the result by Cordeiro and Cordeiro (2001 Cordeiro , H. H. , Cordeiro , G. M. ( 2001 ). Skewness for parameters in generalized linear models . Commun. Statist. Theor. Meth. 30 : 1317 – 1334 .[Taylor & Francis Online], [Web of Science ®] , [Google Scholar]). The formula is given in matrix notation and is very suitable for computer implementation and to obtain closed form expressions for a great variety of models. Some special cases and two applications are discussed.     

Inferences for Mixtures of Distributions for Centrally Censored Data with Partial Identification

In this article, several methods to make inferences about the parameters of a finite mixture of distributions in the context of centrally censored data with partial identification are revised. These methods are an adaptation of the work in Contreras-Cristán, Gutiérrez-Peña, and O'Reilly (2003 Contreras-Cristán , A. , Gutiérrez-Peña , E. , O'Reilly , F. ( 2003 ). Inferences using latent variables for mixtures of distributions for censored data with partial identification . Comm. Stat. Theor. Meth. 32 ( 4 ): 749 – 774 .[Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) in the case of right censoring. The first method focuses on an asymptotic approximation to a suitably simplified likelihood using some latent quantities; the second method is based on the expectation-maximization (EM) algorithm. Both methods make explicit use of latent variables and provide computationally efficient procedures compared to non-Bayesian methods that deal directly with the full likelihood of the mixture appealing to its asymptotic approximation. The third method, from a Bayesian perspective, uses data augmentation to work with an uncensored sample. This last method is related to a recently proposed Bayesian method in Baker, Mengersen, and Davis (2005 Baker , P. , Mengersen , K. , Davis , G. ( 2005 ). A Bayesian solution to reconstructing centrally censored distributions . J. Agr. Biol. Environ. Stat. 1 : 61 – 84 . [Google Scholar]). Our proposal of the three adapted methods is shown to provide similar inferential answers, thus offering alternative analyses.     

A Test of Independence in Two-Way Contingency Tables Based on Maximal Correlation

Maximal correlation has several desirable properties as a measure of dependence, including the fact that it vanishes if and only if the variables are independent. Except for a few special cases, it is hard to evaluate maximal correlation explicitly. We focus on two-dimensional contingency tables and discuss a procedure for estimating maximal correlation, which we use for constructing a test of independence. We compare the maximal correlation test with other tests of independence by Monte Carlo simulations. When the underlying continuous variables are dependent but uncorrelated, we point out some cases for which the new test is more powerful.     

A non stochastic ridge regression estimator and comparison with the James-Stein estimator

Abstract

This article presents a non-stochastic version of the Generalized Ridge Regression estimator that arises from a discussion of the properties of a Generalized Ridge Regression estimator whose shrinkage parameters are found to be close to their upper bounds. The resulting estimator takes the form of a shrinkage estimator that is superior to both the Ordinary Least Squares estimator and the James-Stein estimator under certain conditions. A numerical study is provided to investigate the range of signal to noise ratio under which the new estimator dominates the James-Stein estimator with respect to the prediction mean square error.     

A simple method to identify significant effects in unreplicated two-level factorial designs

this article proposes a generalitation and improvement on the method of lenth (1989). the problem is solved by fixing outliers in highly contaminated samples. to do this a scale robust estimator is obtained and its performance is analyzed using computer simulations. the method is extremely simple to use and leads to the same results as the more complex one proposed by box and meyer(1986).     

Kernel density estimation using weighted data ∗

In this paper we compare the kernel density estimators proposed by Bhattacharyya et al. (1988) and Jones (1991) for length biased data, showing the asymptotic normality of the estimators. A method to construct a new estimator is proposed. Moreover, we extend these results to weighted data and we study an estimator for the weight function.     

Forced cooperation from above: the case of Sweden's establishment reform

In December 2010, significant parts of Swedish integration policy were changed. Through the ‘establishment reform’, a centralization was implemented in which the national level overtook the responsibility of municipalities for the establishment of newly arrived immigrants. In today's system, the responsibility is shared between several authorities, the municipalities, and publicly financed private actors. Recent governmental reports have described the current situation as being characterized by coordination problems and shortcomings in accountability. This policy creates an institutional landscape that spans both vertical and horizontal dimensions, reflecting several levels of the public administration and actors that originate from several sectors. The purpose of this article is to explore the governance of Swedish integration policy, with a theoretical focus derived from the ideal types of hierarchy, market, and network. We examine one Swedish region in which parts of the establishment reform were applied as a pilot project before being applied to the rest of Sweden. The theoretically driven results are unexpected in that they reveal traits of governance steering but also of top-down perspectives and restrictions for involved actors in a way that counteracts theoretical logics.     

Research Review: Risk and resilience in cases of emotional abuse

This paper examines risk and resilience in relation to emotional abuse. Research has identified numerous child and family factors that may increase the risk of emotional abuse occurring and has also identified numerous ways in which an experience of emotional abuse can enhance vulnerability to negative outcomes. However, relatively little is known about the factors that determine the extent to which an experience of emotional abuse predicts later psychosocial functioning. Factors that may determine risk and resilience in children who experience emotional abuse are discussed. These include predisposing factors such as early caregiving experiences; precipitating factors such as the frequency, intensity and duration of the abuse; factors intrinsic to the child such as working models of the self and others, internal or external attributions, behavioural and coping strategies, self‐esteem, and disposition; and external factors such as school and availability of supportive relationships. The need to pay attention to the particular vulnerabilities and protective factors pertaining to each emotionally abused child in order to most effectively enhance resilience is highlighted.     

National pension systems and mass opinion: a case study of confidence, satisfaction and political attitudes in Norway

It is commonly assumed that popular support for national pension systems depends on widespread satisfaction with projected benefit levels among the working age population, and in particular that public support for the system will be jeopardised if the taxpayers do not feel confident about eventually receiving the promised benefits. On the basis of Norwegian survey data, two sets of questions are addressed in the article: (1) Is there a widespread lack of confidence in and satisfaction with the Norwegian National Insurance pension scheme? and (2) Is there an association between confidence and satisfaction and people's political attitudes towards the National Insurance pension scheme? Although we do not find any signs of a dramatic erosion of confidence towards the system, we do find that overall satisfaction with projected benefits is low among the working age population. Contrary to what one might expect, however, confidence and satisfaction from the point of view of individual interests appear not to be associated with a political preference for privatisation.