首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   30篇
  免费   2篇
管理学   6篇
民族学   2篇
人口学   2篇
社会学   18篇
统计学   4篇
  2023年   1篇
  2022年   1篇
  2021年   2篇
  2019年   3篇
  2018年   4篇
  2016年   3篇
  2015年   1篇
  2013年   5篇
  2012年   1篇
  2011年   1篇
  2009年   2篇
  2008年   2篇
  2007年   1篇
  2003年   2篇
  2001年   1篇
  1999年   1篇
  1982年   1篇
排序方式: 共有32条查询结果,搜索用时 15 毫秒
1.
This article describes how a frequentist model averaging approach can be used for concentration–QT analyses in the context of thorough QTc studies. Based on simulations, we have concluded that starting from three candidate model families (linear, exponential, and Emax) the model averaging approach leads to treatment effect estimates that are quite robust with respect to the control of the type I error in nearly all simulated scenarios; in particular, with the model averaging approach, the type I error appears less sensitive to model misspecification than the widely used linear model. We noticed also few differences in terms of performance between the model averaging approach and the more classical model selection approach, but we believe that, despite both can be recommended in practice, the model averaging approach can be more appealing because of some deficiencies of model selection approach pointed out in the literature. We think that a model averaging or model selection approach should be systematically considered for conducting concentration–QT analyses. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
2.
Using networks as prior knowledge to guide model selection is a way to reach structured sparsity. In particular, the fused lasso that was originally designed to penalize differences of coefficients corresponding to successive features has been generalized to handle features whose effects are structured according to a given network. As any prior information, the network provided in the penalty may contain misleading edges that connect coefficients whose difference is not zero, and the extent to which the performance of the method depend on the suitability of the graph has never been clearly assessed. In this work we investigate the theoretical and empirical properties of the adaptive generalized fused lasso in the context of generalized linear models. In the fixed \(p\) setting, we show that, asymptotically, adding misleading edges in the graph does not prevent the adaptive generalized fused lasso from enjoying asymptotic oracle properties, while forgetting suitable edges can be more problematic. These theoretical results are complemented by an extensive simulation study that assesses the robustness of the adaptive generalized fused lasso against misspecification of the network as well as its applicability when theoretical coefficients are not exactly equal. Our contribution is also to evaluate the applicability of the generalized fused lasso for the joint modeling of multiple sparse regression functions. Illustrations are provided on two real data examples.  相似文献   
3.
Health Risk Assessment of a Modern Municipal Waste Incinerator   总被引:2,自引:0,他引:2  
During the modernization of the municipal waste incinerator (MWI, maximum capacity of 180,000 tons per year) of Metropolitan Grenoble (405,000 inhabitants), in France, a risk assessment was conducted, based on four tracer pollutants: two volatile organic compounds (benzene and 1, 1, 1 trichloroethane) and two heavy metals (nickel and cadmium, measured in particles). A Gaussian plume dispersion model, applied to maximum emissions measured at the MWI stacks, was used to estimate the distribution of these pollutants in the atmosphere throughout the metropolitan area. A random sample telephone survey (570 subjects) gathered data on time-activity patterns, according to demographic characteristics of the population. Life-long exposure was assessed as a time-weighted average of ambient air concentrations. Inhalation alone was considered because, in the Grenoble urban setting, other routes of exposure are not likely. A Monte Carlo simulation was used to describe probability distributions of exposures and risks. The median of the life-long personal exposures distribution to MWI benzene was 3.2·10–5 g/m3 (20th and 80th percentiles = 1.5·10–5 and 6.5·10–5 g/m3), yielding a 2.6·10–10 carcinogenic risk (1.2·10–10–5.4·10–10). For nickel, the corresponding life-time exposure and cancer risk were 1.8·10–4 g/m3 (0.9.10–4 – 3.6·10–4 g/m3) and 8.6·10–8 (4.3·10–8–17.3·10–8); for cadmium they were respectively 8.3·10–6 g/m3 (4.0·10–6–17.6·10–6) and 1.5·10–8 (7.2·10–9–3.1·10–8). Inhalation exposure to cadmium emitted by the MWI represented less than 1% of the WHO Air Quality Guideline (5 ng/m3), while there was a margin of exposure of more than 109 between the NOAEL (150 ppm) and exposure estimates to trichloroethane. Neither dioxins nor mercury, a volatile metal, were measured. This could lessen the attributable life-long risks estimated. The minute (VOCs and cadmium) to moderate (nickel) exposure and risk estimates are in accord with other studies on modern MWIs meeting recent emission regulations, however.  相似文献   
4.
5.
In this article, we use the intersubjective ethics of Bakhtin and Levinas and a case illustration to explore change in therapy as an ethical phenomenon. We follow Lakoff and Johnson in their emphasis on the way our conceptions of change seem permeated by metaphors. Bakhtin and Levinas both suggest through a language in which metaphors play a crucial role, that human existence—the consciousness and the subject—emerge within the dialogue of the encounter. They both describe the dynamics of human existence as ethical in their origin. Following this, we argue that change may be seen as an ongoing ethical event and that the dynamics of change are found in the ways we constantly become in this event. We investigate the ethical dynamics of this ongoing event through three themes illuminating the contributions of both Bakhtin and Levinas: (1) we become as responsible, (2) we become in speaking, (3) we become in answering the unknown. We explore these themes through a case illustration. Finally, we briefly point out some possible implications for mental health practice.  相似文献   
6.
7.
Population and Environment - This paper presents a transdisciplinary study focusing on the socio-ecological mechanisms at play in the alteration of Moorea’s (French Polynesia) coastline....  相似文献   
8.
The commodity nature of green coffee is the main cause of the ‘coffee paradox’ (falling producer prices and rising consumer prices). Geographical Indications (GIs) may be an effective ‘decommodifier’ of the coffee market, but many constraints have to be overcome. Based on an analysis of how the characteristics of the coffee production system shape the positions of local stakeholders and, thus, the GI building process, this article identifies some constraining factors that can seriously undermine the capacity the GI has to decommodify the market and attain a fairer distribution of the benefits for local producers.  相似文献   
9.
10.
In the Mediterranean, long-term land-use changes have resulted into landscape mosaics composed of very few ancient woodland remnants scattered across extended post-agricultural woodlands. Patches of ancient woodlands are now suffering rapid urban growth that reduces their area and impact their associated biodiversity. Here we use the case study of Montpellier, one of the most dynamic cities in France, to 1) characterize temporal changes in land covers (between 1860 and 2006) in its area, and 2) using two guilds of fungal bioindicators (i.e., polypores and lichens), to compare biodiversity stakes between ancient and secondary Mediterranean woodlands. We used a combination of historical maps, archives, fungal collections and field survey in eight Quercus ilex patches (4 ancient versus 4 recent replicates) to reconstruct landscapes dynamics and assess biodiversity changes. From the 19th to the 21st century, over half (52.4%) of the ancient woodlands within Montpellier were replaced by other land covers, mainly by urban equipment, while secondary patches (16.8% of the total area) were naturally established. Remaining ancient woodlands show multi-layered vegetation made of multi-secular Pinus halepensis dominating a dynamic understorey made of Quercus ilex and various Mediterranean shrubs. Polypores, but not macrolichens, tended to differ in community composition between ancient and recent woodland patches, with the highest diversity found in ancient woodlands. This study highlights that urban woodland patches of contrasted histories harbour distinct biodiversity stakes to be included in urban planning and provide valuable areas to evaluate biodiversity patterns and dynamics.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号