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31.
This article examines the occupational mobility of immigrants between their countries of origin and Spain on the basis of one of the few surveys available internationally with longitudinal information on immigrant employment in home and host countries. The evidence shows that the occupational status of immigrants in the Spanish labour market is, in general, substantially worse than in their countries of origin. The severe loss of occupational status experienced by immigrants is explained by the combined effect of the intense initial downgrading they experience when entering the Spanish labour market and their very slow occupational progress during their stay in Spain. These findings are more in line with the segmented assimilation theory, which suggests a limited or blocked immigrant occupational mobility, than with the assimilation theory, which predicts a U shaped evolution in the occupational status of immigrants between their home and host countries. As a result, the Spanish case contrasts sharply with previous evidence for other advanced countries, which tends to support the assimilation perspective. Finally, the empirical evidence suggests that one of the elements impeding the occupational mobility of immigrants in Spain is the significant size of the secondary segment of the labour market, which restricts immigrants’ opportunities mainly to low-status occupations.  相似文献   
32.
    
We, the Editors and Publisher of National Identities, have retracted the following book review:

Pedro García-Guirao (2019)

Book Review of The victorious counterrevolution: the nationalist effort in the Spanish Civil War. National Identities, published online on 14th February 2019, DOI:10.1080/14608944.2018.1563986

The above-mentioned book review contained some inaccuracies in quotations and some statements which may be misleading as to the contents of the book. The book review was subsequently revised and re-published as DOI: 10.1080/14608944.2018.1563986

We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines on retractions.

The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as “Retracted”.  相似文献   
33.
Previous sociological research shows that exposure to stress varies by individuals’ social statuses and is a central mechanism in producing mental health disparities. This line of research suggests that ethnoracial groups are more exposed to racial discrimination, thus negatively impacting their mental health. There has also been a growing literature showing how legal status impacts the mental health of immigrants and their families. However, the sociology of mental health and migration literature has largely remained disparate. This paper bridges these literatures to highlight how living a deportation threat manifests itself as an anticipatory stressor that negatively impacts undocumented Mexican migrant women’s access to resources, social relationships, and social roles. Based on 30 semi-structured in-depth interviews with undocumented Mexican immigrant women from Houston, Texas, my findings reveal living a deportation threat is a perpetual anticipatory stressor that intensifies the effects of avoiding authorities, family fragmentation, and economic uncertainty. I argue this anticipatory stressor transforms into a chronic stressor that undocumented Mexican women confront daily. By situating this study within an anti-immigrant social context, it highlights the social processes and mechanisms that exacerbate the stressors undocumented Mexican immigrant women confront.  相似文献   
34.
    
The hyper‐Poisson distribution can handle both over‐ and underdispersion, and its generalized linear model formulation allows the dispersion of the distribution to be observation‐specific and dependent on model covariates. This study's objective is to examine the potential applicability of a newly proposed generalized linear model framework for the hyper‐Poisson distribution in analyzing motor vehicle crash count data. The hyper‐Poisson generalized linear model was first fitted to intersection crash data from Toronto, characterized by overdispersion, and then to crash data from railway‐highway crossings in Korea, characterized by underdispersion. The results of this study are promising. When fitted to the Toronto data set, the goodness‐of‐fit measures indicated that the hyper‐Poisson model with a variable dispersion parameter provided a statistical fit as good as the traditional negative binomial model. The hyper‐Poisson model was also successful in handling the underdispersed data from Korea; the model performed as well as the gamma probability model and the Conway‐Maxwell‐Poisson model previously developed for the same data set. The advantages of the hyper‐Poisson model studied in this article are noteworthy. Unlike the negative binomial model, which has difficulties in handling underdispersed data, the hyper‐Poisson model can handle both over‐ and underdispersed crash data. Although not a major issue for the Conway‐Maxwell‐Poisson model, the effect of each variable on the expected mean of crashes is easily interpretable in the case of this new model.  相似文献   
35.
    
The relation between change points in multivariate surveillance is important but seldom considered. The sufficiency principle is here used to clarify the structure of some problems, to find efficient methods, and to determine appropriate evaluation metrics. We study processes where the changes occur simultaneously or with known time lags. The surveillance of spatial data is one example where known time lags can be of interest. A general version of a theorem for the sufficient reduction of processes that change with known time lags is given. A simulation study illustrates the benefits or the methods based on the sufficient statistics.  相似文献   
36.
    
The relationship between contributions and elicited beliefs in a repeated two-person public good experiment is modeled with the help of a parsimounious random-utility function that allows for conditionally cooperative, opportunistic, and altruistic patterns of behavior. Under standard assumptions, a latent-class mixed logit specification with three sub-populations is shown to capture well heterogeneity in individual contribution levels over time, while also accomodating for different degrees of heteroscedasticity. The estimation results are consistent with the conjecture that the majority of players in public goods games are strongly conditional cooperators, with smaller fractions of the population leaning to opportunistic or altruistic behavior.  相似文献   
37.
    
ABSTRACT

We introduce a semi-parametric Bayesian approach based on skewed Dirichlet processes priors for location parameters in the ordinal calibration problem. This approach allows the modeling of asymmetrical error distributions. Conditional posterior distributions are implemented, thus allowing the use of Markov chains Monte Carlo to generate the posterior distributions. The methodology is applied to both simulated and real data.  相似文献   
38.
    
Abstract

The notions of (sample) mean, median and mode are common tools for describing the central tendency of a given probability distribution. In this article, we propose a new measure of central tendency, the sample monomode, which is related to the notion of sample mode. We also illustrate the computation of the sample monomode and propose a statistical test for discrete monomodality based on the likelihood ratio statistic.  相似文献   
39.
    
The quality of the asymptotic normality of realized volatility can be poor if sampling does not occur at very high frequencies. In this article we consider an alternative approximation to the finite sample distribution of realized volatility based on Edgeworth expansions. In particular, we show how confidence intervals for integrated volatility can be constructed using these Edgeworth expansions. The Monte Carlo study we conduct shows that the intervals based on the Edgeworth corrections have improved properties relatively to the conventional intervals based on the normal approximation. Contrary to the bootstrap, the Edgeworth approach is an analytical approach that is easily implemented, without requiring any resampling of one's data. A comparison between the bootstrap and the Edgeworth expansion shows that the bootstrap outperforms the Edgeworth corrected intervals. Thus, if we are willing to incur in the additional computational cost involved in computing bootstrap intervals, these are preferred over the Edgeworth intervals. Nevertheless, if we are not willing to incur in this additional cost, our results suggest that Edgeworth corrected intervals should replace the conventional intervals based on the first order normal approximation.  相似文献   
40.
    
Suppose that data {(x l,i,n , y l,i,n ): l?=?1, …, k; i?=?1, …, n} are observed from the regression models: Y l,i,n ?=?m l (x l,i,n )?+?? l,i,n , l?=?1, …, k, where the regression functions {m l } l=1 k are unknown and the random errors {? l,i,n } are dependent, following an MA(∞) structure. A new test is proposed for testing the hypothesis H 0: m 1?=?·?·?·?=?m k , without assuming that {m l } l=1 k are in a parametric family. The criterion of the test derives from a Crámer-von-Mises-type functional based on different distances between {[mcirc]} l and {[mcirc]} s , l?≠?s, l, s?=?1, …, k, where {[mcirc] l } l=1 k are nonparametric Gasser–Müller estimators of {m l } l=1 k . A generalization of the test to the case of unequal design points, with different sample sizes {n l } l=1 k and different design densities {f l } l=1 k , is also considered. The asymptotic normality of the test statistic is obtained under general conditions. Finally, a simulation study and an analysis with real data show a good behavior of the proposed test.  相似文献   
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