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261.
H. William Amos 《Journal of Sociolinguistics》2020,24(1):55-74
In recent decades, sociolinguists have begun to challenge the traditional view that multilingualism is fundamentally composed of discrete systems known as ‘languages’. Supporting the assessment that languages are not bounded entities but sociocultural and ideological constructions, this article explores commercial advertisements in France, which are subject to language policies assuming that ‘French’ is easily separable from ‘foreign languages’. Employing the Bakhtinian‐influenced notion of bivalency developed by Woolard (1998), the article argues for a special consideration of mixed‐language advertising in France, rooted not only in linguistic form, but also in the specific contextual tension produced by the socio‐political statuses of French and English. The resulting creativity challenges the monolectal assumptions within French language management, indicating a clash of segregational language ideology with integrational language practices. The article further argues that this language mixing is bidirectional, as advertisements may both erase and emphasise the assumed boundaries between codes. 相似文献
262.
Individual differences in infants’ engagement with their environment manifest early in development and are noticed by parents. Three views have been advanced to explain differences in seeking novel stimulation. The optimal stimulation hypothesis suggests that individuals seek further stimulation when they are under‐responsive to current sensory input. The processing speed hypothesis proposes that those capable of processing information faster are driven to seek stimulation more frequently. The information prioritization hypothesis suggests the differences in stimulation seeking index variation in the prioritization of incoming relative to ongoing information processing. Ten‐month‐old infants saw 10 repetitions of a video clip and changes in frontal theta oscillatory amplitude were measured as an index of information processing speed. Stimulus‐locked P1 peak amplitude in response to checkerboards briefly overlaid on the video at random points during its presentation indexed processing of incoming stimulation. Parental report of higher visual seeking did not relate to reduced P1 peak amplitude or to a stronger decrease in frontal theta amplitude with repetition, thus not supporting either the optimal stimulation or the processing speed hypotheses. Higher visual seeking occurred in those infants whose P1 peak amplitude was greater than expected based on their theta amplitude. These findings indicate that visual sensory seeking in infancy is explained by a bias toward novel stimulation, thus supporting the information prioritization hypothesis. 相似文献
263.
To perform variable selection in expectile regression, we introduce the elastic-net penalty into expectile regression and propose an elastic-net penalized expectile regression (ER-EN) model. We then adopt the semismooth Newton coordinate descent (SNCD) algorithm to solve the proposed ER-EN model in high-dimensional settings. The advantages of ER-EN model are illustrated via extensive Monte Carlo simulations. The numerical results show that the ER-EN model outperforms the elastic-net penalized least squares regression (LSR-EN), the elastic-net penalized Huber regression (HR-EN), the elastic-net penalized quantile regression (QR-EN) and conventional expectile regression (ER) in terms of variable selection and predictive ability, especially for asymmetric distributions. We also apply the ER-EN model to two real-world applications: relative location of CT slices on the axial axis and metabolism of tacrolimus (Tac) drug. Empirical results also demonstrate the superiority of the ER-EN model. 相似文献
264.
The importance of sensitivity analysis information in linear programming has been stressed in the management science literature for some time. Indeed, Gal [3] has devoted an entire text to just this issue. Linear programs with common inputs (cost coefficients or right-hand-side values) present a problem in that classical sensitivity analysis does not allow for the simultaneous changes required to determine the sensitivity of these models to common inputs. We first survey the approaches previously developed for simultaneous-change sensitivity analysis and cast them in the framework of the special common input case. These general techniques are compared to a simple aggregate variable technique that has not received attention in the literature. 相似文献
265.
A. Kheyri H. Jabbari A. Bozorgnia 《Journal of Statistical Computation and Simulation》2019,89(12):2373-2392
In this paper, the kernel density estimator for negatively superadditive dependent random variables is studied. The exponential inequalities and the exponential rate for the kernel estimator of density function with a uniform version, over compact sets are investigated. Also, the optimal bandwidth rate of the estimator is obtained using mean integrated squared error. The results are generalized and used to improve the ones obtained for the case of associated sequences. As an application, FGM sequences that fulfil our assumptions are investigated. Also, the convergence rate of the kernel density estimator is illustrated via a simulation study. Moreover, a real data analysis is presented. 相似文献
266.
Hadi Alizadeh Noughabi 《Journal of Statistical Computation and Simulation》2019,89(10):1914-1934
We propose here a general statistic for the goodness of fit test of statistical distributions. The proposed statistic is constructed based on an estimate of Kullback–Leibler information. The proposed test is consistent and the limiting distribution of the test statistic is derived. Then, the established results are used to introduce goodness of fit tests for the normal, exponential, Laplace and Weibull distributions. A simulation study is carried out for examining the power of the proposed test and to compare it with those of some existing procedures. Finally, some illustrative examples are presented and analysed, and concluding comments are made. 相似文献
267.
Bartlett correction constitutes one of the attractive features of empirical likelihood because it enables the construction of confidence regions for parameters with improved coverage probabilities. We study the Bartlett correction of spatial frequency domain empirical likelihood (SFDEL) based on general spectral estimating functions for regularly spaced spatial data. This general formulation can be applied to testing and estimation problems in spatial analysis, for example testing covariance isotropy, testing covariance separability as well as estimating the parameters of spatial covariance models. We show that the SFDEL is Bartlett correctable. In particular, the improvement in coverage accuracies of the Bartlett‐corrected confidence regions depends on the underlying spatial structures. The Canadian Journal of Statistics 47: 455–472; 2019 © 2019 Statistical Society of Canada 相似文献
268.
T. H. M. Abouelmagd A. A. E. Ahmed Enayat M. Abd Elrazik Mahmoud M. Mansour A-Hadi N. Ahmed 《统计学通讯:理论与方法》2019,48(12):2904-2916
In this paper, a comparison between the life distribution of a new unit with that of a used unit in the increasing convex order is made leading to a new class of life distributions which we call “new better than used in convex ordering of second order”. This class includes as subclasses the NBU and the NBUC and is a subclass of the NBUCA class. Preservation properties under convolution, random maxima, mixing and formation of coherent structures are established. Stochastic comparisons of the excess lifetime when the inter-arrival times belong to the NBUC(2) class are developed. Some applications of Poisson shock models and a test of exponentiality against NBUC(2) alternative are presented. 相似文献
269.
Lifetime Data Analysis - 相似文献
270.
We examined social and economic resources in the environments of children involved with child protective services and their associations with children's cognitive performance. We used a national dataset of child protection investigations (children aged 6–16 at Wave 1). Using latent class analysis, we constructed profiles of the financial resources, parental education and employment, and family structure and size. We then examined within‐ and across‐time associations between resource environment profiles and children's math and reading scores and tested whether associations differed by family care type. Our latent class analysis identified four distinct family resource environments: educated middle class, single earner, large working class, and severely disadvantaged. Family resource environment profiles predicted current cognitive performance and changes in performance over time, but associations were more consistent for children in biological family care. Children who remain in home following maltreatment allegations may benefit from services that target social as well as economic resources. 相似文献