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901.
This paper studies the outlier detection and robust variable selection problem in the linear regression model. The penalized weighted least absolute deviation (PWLAD) regression estimation method and the adaptive least absolute shrinkage and selection operator (LASSO) are combined to simultaneously achieve outlier detection, and robust variable selection. An iterative algorithm is proposed to solve the proposed optimization problem. Monte Carlo studies are evaluated the finite-sample performance of the proposed methods. The results indicate that the finite sample performance of the proposed methods performs better than that of the existing methods when there are leverage points or outliers in the response variable or explanatory variables. Finally, we apply the proposed methodology to analyze two real datasets.  相似文献   
902.
In high-dimensional linear regression, the dimension of variables is always greater than the sample size. In this situation, the traditional variance estimation technique based on ordinary least squares constantly exhibits a high bias even under sparsity assumption. One of the major reasons is the high spurious correlation between unobserved realized noise and several predictors. To alleviate this problem, a refitted cross-validation (RCV) method has been proposed in the literature. However, for a complicated model, the RCV exhibits a lower probability that the selected model includes the true model in case of finite samples. This phenomenon may easily result in a large bias of variance estimation. Thus, a model selection method based on the ranks of the frequency of occurrences in six votes from a blocked 3×2 cross-validation is proposed in this study. The proposed method has a considerably larger probability of including the true model in practice than the RCV method. The variance estimation obtained using the model selected by the proposed method also shows a lower bias and a smaller variance. Furthermore, theoretical analysis proves the asymptotic normality property of the proposed variance estimation.  相似文献   
903.
张焰 《民族研究》2001,(2):40-49
本文叙述了建国后石柱县各阶段人口发展的情形以及目前石柱县的人口生育模式等人口状况。研究分析表明,影响石柱县人口发展变化的主要因素是经济和政策因素;在不同时期,这两种因素所起的作用是不同的;而在现今的石柱县,政策因素对人口发展的影响占据着主导地位。  相似文献   
904.
Quality of life is a complicated concept that has attracted broad attention from multiple disciplines. This article introduces a set of studies that employ diverse approaches to explore how work, vocational, and career experiences shape quality of life among migrants, and proposes a future agenda to extend this stream of research. Specifically, operationalizing quality of life in different ways, research showcased in this special issue has demonstrated how international and intranational migrants achieve, maintain, and enhance their well-being in different life domains. Reflecting on the literature and the showcased studies, this article proposes that future research should advance the current inquiry by better categorizing vocational experiences, uniquely operationalizing of quality of life in migration contexts, taking a more culturally sensitive perspective, and broadening methodological approaches.  相似文献   
905.
This paper investigates the impact of pension income on living arrangements of the elderly. Taking advantage of a unique opportunity due to the recent establishment and expansion of the New Rural Pension Scheme in China, we explicitly address the endogeneity of pension status and pension income through a fixed-effect model with instrumental variable approach by exploiting exogenous time variation in the program implementation at county level. We find an overall positive effect of pension income on independent living as well as considerable heterogeneity. The positive income effects of the NRPS are concentrated among the elderly with adult children living nearby, of higher socio-economic status, and with better health at baseline; for other groups, the effects are insignificant. We also find that more generous programs exhibit larger effects. Our results highlight that living arrangement is multidimensional in rural China.  相似文献   
906.
“互联网+”、3D打印技术为代表的信息化浪潮已经到来,创新创业教育的已经在全国展开,这既是高等教育教学的挑战,更是不可多得的机遇。为适应信息技术的需求,高等院校要未雨绸缪,及时应对,从创新体系构建信息技术要先行、教育教学创新体系构建要结合学科、专业特点进行、二级学院联动、对教师要求及激励等多个方面探讨信息技术背景下教育教学多维度创新体系。  相似文献   
907.
We aimed to apply syndemic theory to verify the association and reinforcing effects between psychosocial problems and multiple sexual partners (MSP) of men who have sex with men (MSM) in Shanghai, China. A cross-sectional study was conducted among 547 MSM in Shanghai, China using a face-to-face survey. Sociodemographic and psychosocial data were collected, as well as information on MSP and condomless anal sex. In the 6 months prior to the survey, 54.3% of the MSM sample had had MSP. Univariate analysis showed that self-esteem, depression, loneliness, sexual compulsivity, and involuntary subordination (IS) were associated with MSP. Sexual compulsivity (multivariate odds ratio [ORm] = 2.94, 95% CI = 1.76–4.91) and IS (ORm = 1.79, 95% CI = 1.14–2.81) remained significant in multivariate analysis. MSM with five or more psychosocial problems had greater odds of (adjusted odds ratios = 3.06, 95% CI = 1.49–6.25) having MSP in the previous 6 months than the non-syndemic group. Our findings provide preliminary confirmation of the additive relationship of syndemic psychosocial health conditions and MSP among MSM in Shanghai, China. An integrated intervention with special focus on sexual compulsivity and IS is needed.  相似文献   
908.
This article offers a framework for exploring the relevance of modernity to contemporary East Asia. I first examine different conceptualizations of modernity, paying special attention to Eisenstadt's influential concept of multiple modernities. Second, I point out the limitations and flaws of Eisenstadt's theory by drawing on nationalist politics in East Asia as an illustrative case. In particular, I examine the so-called “history perception problem,” which has been created by war and shaped by the legacies of war, to demonstrate the peculiar features of modernity in East Asia. Third, I use the works by three scholars as examples to show how intellectuals in China, South Korea, and Taiwan respond to the tensions between universalism and particularism, which, as a whole, reflect what can be called “East Asian modernity.” And finally, I try to respond to the controversial but fashionable question that is peculiar to East Asia: can modernity be overcome? It is argued that East Asia can be understood through the lens of modernity, and vice versa. Nowadays, modernity has become a global condition in both geographical and topological senses. It is not something to be overcome, but a condition that we all live in and should learn to live with, here and now.  相似文献   
909.
A graph \(G=(V,E)\) with even number vertices is called Pfaffian if it has a Pfaffian orientation, namely it admits an orientation such that the number of edges of any M-alternating cycle which have the same direction as the traversal direction is odd for some perfect matching M of the graph G. In this paper, we obtain a necessary and sufficient condition of Pfaffian graphs in a type of bipartite graphs. Then, we design an \(O(|E(G)|^2)\) algorithm for recognizing Pfaffian graphs in this class and constructs a Pfaffian orientation if the graph is Pfaffian. The results improve and generalize some known results.  相似文献   
910.
We propose a new typology of paternalistic leadership styles based on how leaders demonstrate authoritarianism and benevolence, the two essential components of this type of leadership. Benevolence-dominant paternalistic leadership refers to leaders' sole dependence on the use of benevolence without their strong assertion of authority, whereas authoritarianism-dominant paternalistic leadership is based mainly on authoritarianism itself; classical paternalistic leadership, which best fits early observations of paternalistic leaders, refers to the salient combination of both leadership components. We used two distinct samples and methods to test this typology and the association with subordinate performance. Across the two studies, a field investigation with Taiwanese military supervisor-subordinate dyads and a hypothetical scenario experiment with U.S. working adults, we found a positive relationship between classical paternalistic leadership and subordinate performance as strong as that between benevolence-dominant paternalistic leadership and performance. Our findings echo the phenomenon that paternalistic leaders tend to combine benevolence with authoritarianism to affect subordinate performance.  相似文献   
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