In many practical applications, high-dimensional regression analyses have to take into account measurement error in the covariates. It is thus necessary to extend regularization methods, that can handle the situation where the number of covariates p largely exceed the sample size n, to the case in which covariates are also mismeasured. A variety of methods are available in this context, but many of them rely on knowledge about the measurement error and the structure of its covariance matrix. In this paper, we set the goal to compare some of these methods, focusing on situations relevant for practical applications. In particular, we will evaluate these methods in setups in which the measurement error distribution and dependence structure are not known and have to be estimated from data. Our focus is on variable selection, and the evaluation is based on extensive simulations. 相似文献
Children are central to the rhetoric supporting global climate agreements, yet they are also envisaged to play a strategic role in materialising such agreements. Along with other household actors, children are implicated in localised efforts to manage global resource sustainability. As learners in educational systems that are being redesigned to encompass messages of sustainability, children are moreover positioned as ‘agents of change’ through sustainability education. Drawing on theoretical work on children's agency and interdependence, this review calls for greater attention to the structural and relational dimensions of environmental knowledge transmission to inform sustainability education. This is presented as one move towards constructing what Middlemiss (2014) terms a more ‘socially sensitive’ model of sustainable development. 相似文献
By adopting a multidimensional approach to environmental attitudes (apathy, anthropocentrism, connectedness and emotional affinity with nature), this study explores the relationships between these dimensions, social dominance orientation (SDO) and political orientation. Two hundred and sixty-two Chilean university students filled out an ad hoc online questionnaire. Two confirmatory factorial analyses showed the four typologies of environmental attitudes and the two factors for SDO, which are labelled group dominance and opposition to equality. Through hierarchical regressions, group dominance showed higher explanatory power of environmental attitudes than political orientation. Furthermore, using the bootstrap procedure we showed that group dominance mediated between political orientation and attitudes of apathy, anthropocentrism and connectedness, while opposition to equality mediated between apathy and emotional affinity. We conclude that SDO is an important variable for measuring political ideology while also providing new nuances when analysing the relationships with environmental attitudes. 相似文献
The aim of this study is to estimate the reference level of lifetime cadmium intake (LCd) as the benchmark doses (BMDs) and their 95% lower confidence limits (BMDLs) for various renal effects by applying a hybrid approach. The participants comprised 3,013 (1,362 men and 1,651 women) and 278 (129 men and 149 women) inhabitants of the Cd‐polluted and nonpolluted areas, respectively, in the environmentally exposed Kakehashi River basin. Glucose, protein, aminonitrogen, metallothionein, and β2‐microglobulin in urine were measured as indicators of renal dysfunction. The BMD and BMDL that corresponded to an additional risk of 5% were calculated with background risk at zero exposure set at 5%. The obtained BMDLs of LCd were 3.7 g (glucose), 3.2 g (protein), 3.7 g (aminonitrogen), 1.7 g (metallothionein), and 1.8 g (β2‐microglobulin) in men and 2.9 g (glucose), 2.5 g (protein), 2.0 g (aminonitrogen), 1.6 g (metallothionein), and 1.3 g (β2‐microglobulin) in women. The lowest BMDL was 1.7 g (metallothionein) and 1.3 g (β2‐microglobulin) in men and women, respectively. The lowest BMDL of LCd (1.3 g) was somewhat lower than the representative threshold LCd (2.0 g) calculated in the previous studies. The obtained BMDLs may contribute to further discussion on the health risk assessment of cadmium exposure. 相似文献
Background: The majority of people with dementia are cared for by their families at home. This study aimed to elicit family carers' perceptions on home environmental aspects and strategies with the view to identify barriers and facilitators when caring for a person with dementia at home.
Design and methods: Thirteen co-resident family carers were engaged in semi-structured in-depth walking interviews. Interviews were recorded, transcribed and analysed using thematic analysis.
Results: Home environments can pose a number of challenges and opportunities. Aspects of the architectural and interior environment (e.g. size, condition, layout and accessibility, familiarity) are perceived as important (Theme 1) as well as a plethora of environmental strategies that encourage independence and comfort at home (Theme 2). Carers' scepticism, timing, costs, property characteristics and mistrust to services are some barriers to implementing environmental strategies (Theme 3).
Conclusions: Carers improvised solutions via trial and error and need further education on strategies to create an enabling and comfortable home environment. 相似文献