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Theory and Society - 相似文献
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Whereas prior research focused on the beneficial effects of time spent with others, this study investigated the association between solitary time and mental health by hypothesizing about the possible detriments as well as benefits. Additionally, we studied whether the association between solitary time and mental health was nonlinear and moderated by gender and life stage. We hypothesized that whereas solitary time limits individuals’ access to social resources and support (decreasing mental health), it also helps individuals to recharge (enhancing mental health). We used the Dutch Time Use Survey from 2006 (N = 1,487). Results of Tobit models indicated that more solitary time in leisure (but not household labor) was associated with a reduction in mental health. For men, we did find a negative association between alone time in household labor and mental health. There was no evidence for a curvilinear relationship between time alone and mental health, nor did life course stage appeared to moderate this association. 相似文献
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A novel approach to pure 0-1 integer programming problems called Resolution Search has been proposed by Chvatal (Discrete Applied Mathematics, vol. 73, pp. 81–99, 1997) as an alternative to implicit enumeration, with a demonstration that the method can yield more effective branching strategies. We show that an earlier method called Dynamic Branch-and-Bound (B&B) yields the same branching strategies as Resolution Search, and other strategic alternatives in addition. Moreover, Dynamic B&B is not restricted to pure 0-1 problems, but applies to general mixed integer programs containing both general integer and continuous variables.We provide examples comparing Resolution Search to enhanced variants. We also show the relation of these approaches to Dynamic B&B, suggesting the value of further study of this neglected approach. 相似文献
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Gibbs point processes (GPPs) constitute a large and flexible class of spatial point processes with explicit dependence between the points. They can model attractive as well as repulsive point patterns. Feature selection procedures are an important topic in high-dimensional statistical modeling. In this paper, a composite likelihood (in particular pseudo-likelihood) approach regularized with convex and nonconvex penalty functions is proposed to handle statistical inference for possibly high-dimensional inhomogeneous GPPs. We particularly investigate the setting where the number of covariates diverges as the domain of observation increases. Under some conditions provided on the spatial GPP and on penalty functions, we show that the oracle property, consistency and asymptotic normality hold. Our results also cover the low-dimensional case which fills a large gap in the literature. Through simulation experiments, we validate our theoretical results and finally, an application to a tropical forestry dataset illustrates the use of the proposed approach. 相似文献
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The aim of this paper is to study the asymptotic properties of a class of kernel conditional mode estimates whenever functional stationary ergodic data are considered. To be more precise on the matter, in the ergodic data setting, we consider a random elements (X, Z) taking values in some semi-metric abstract space \(E\times F\). For a real function \(\varphi \) defined on the space F and \(x\in E\), we consider the conditional mode of the real random variable \(\varphi (Z)\) given the event “\(X=x\)”. While estimating the conditional mode function, say \(\theta _\varphi (x)\), using the well-known kernel estimator, we establish the strong consistency with rate of this estimate uniformly over Vapnik–Chervonenkis classes of functions \(\varphi \). Notice that the ergodic setting offers a more general framework than the usual mixing structure. Two applications to energy data are provided to illustrate some examples of the proposed approach in time series forecasting framework. The first one consists in forecasting the daily peak of electricity demand in France (measured in Giga-Watt). Whereas the second one deals with the short-term forecasting of the electrical energy (measured in Giga-Watt per Hour) that may be consumed over some time intervals that cover the peak demand. 相似文献
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We propose a new method for the Maximum Likelihood Estimator (MLE) of nonlinear mixed effects models when the variance matrix
of Gaussian random effects has a prescribed pattern of zeros (PPZ). The method consists of coupling the recently developed
Iterative Conditional Fitting (ICF) algorithm with the Expectation Maximization (EM) algorithm. It provides positive definite
estimates for any sample size, and does not rely on any structural assumption concerning the PPZ. It can be easily adapted
to many versions of EM. 相似文献
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Seantel Anaïs 《Cultural Studies》2016,30(6):949-968
This article provides an account of the nuclear test series carried out at the Nevada Test Site (NTS). We examine how practices of security produce publics and make particular forms of embodiment possible. This account focuses on three key moments to shift the debate on national security projects from audience to public by bringing intra-action and embodiment into the frame. First, we show how atomic testing operated on the terrain of public culture as much as physical territory. Second, we demonstrate how the materiality of the bomb, and its consequences for those who witnessed detonations, reveals the relation between publicity and secrecy as strategies for managing information about security projects. Finally, drawing on Barad's Agential Realism, we use the dosimetry film badge as a device through which to read the relationship between the atomic bomb and its nuclear publics. 相似文献
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Bernard DUHAIME Éloïse DÉCOSTE 《International labour review / International Labour Office》2020,159(4):525-544
This article analyses how the Inter-American System for the protection of human rights has used ILO standards as a reference on matters relating to freedom of association and the rights of indigenous peoples. Having established the limits to their use, the authors also analyse how these standards have influenced recent Inter-American jurisprudence in relation to certain economic, social and cultural rights. They argue that such cross-referencing is both desirable and useful, since it allows the Inter-American bodies to base their arguments on the interpretation of specialized authorities, thereby reinforcing the credibility, normative legitimacy and universality of their decisions. 相似文献
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Piecewise-deterministic Markov processes form a general class of non diffusion stochastic models that involve both deterministic trajectories and random jumps at random times. In this paper, we state a new characterization of the jump rate of such a process with discrete transitions. We deduce from this result a non parametric technique for estimating this feature of interest. We state the uniform convergence in probability of the estimator. The methodology is illustrated on a numerical example. 相似文献