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1.
Married individuals are healthier than single individuals though the reasons are not well understood. Individuals with spouses/or partners are less likely to smoke. We explore the relationship between health and marital status by analyzing three potential channels through which marriage affects smoking, i.e., consumption externalities (one spouse's smoking affects the other spouse's welfare), altruism (one spouse reduces smoking in response to the other spouse's bad health), and learning about risks of smoking from the health experience of one's spouse. We find spousal health does not affect smoking due to altruism or learning within the household but do find evidence for consumption externalities.  相似文献   
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The analysis of survival endpoints subject to right-censoring is an important research area in statistics, particularly among econometricians and biostatisticians. The two most popular semiparametric models are the proportional hazards model and the accelerated failure time (AFT) model. Rank-based estimation in the AFT model is computationally challenging due to optimization of a non-smooth loss function. Previous work has shown that rank-based estimators may be written as solutions to linear programming (LP) problems. However, the size of the LP problem is O(n 2+p) subject to n 2 linear constraints, where n denotes sample size and p denotes the dimension of parameters. As n and/or p increases, the feasibility of such solution in practice becomes questionable. Among data mining and statistical learning enthusiasts, there is interest in extending ordinary regression coefficient estimators for low-dimensions into high-dimensional data mining tools through regularization. Applying this recipe to rank-based coefficient estimators leads to formidable optimization problems which may be avoided through smooth approximations to non-smooth functions. We review smooth approximations and quasi-Newton methods for rank-based estimation in AFT models. The computational cost of our method is substantially smaller than the corresponding LP problem and can be applied to small- or large-scale problems similarly. The algorithm described here allows one to couple rank-based estimation for censored data with virtually any regularization and is exemplified through four case studies.  相似文献   
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For the balanced variance component model when the intraclass correlation coefficient is of interest, Bayesian analysis is often appropriate. Berger and Bernardo’s (1992a) grouped ordering reference prior approach is used to analyze this model. The reference priors are developed and compared for the posterior inference with real and simulated data. We examine whether the reference priors satisfy the probability-matching criterion. Further, the reference prior is shown to be good in the sense of correct frequentist coverage probability of the posterior quantile.  相似文献   
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In analyzing data from unreplicated factorial designs, the half-normal probability plot is commonly used to screen for the ‘vital few’ effects. Recently, many formal methods have been proposed to overcome the subjectivity of this plot. Lawson (1998) (hereafter denoted as LGB) suggested a hybrid method based on the half-normal probability plot, which is a blend of Lenth (1989) and Loh (1992) method. The method consists of fitting a simple least squares line to the inliers, which are determined by the Lenth method. The effects exceeding the prediction limits based on the fitted line are candidates for the vital few effects. To improve the accuracy of partitioning the effects into inliers and outliers, we propose a modified LGB method (hereafter denoted as the Mod_LGB method), in which more outliers can be classified by using both the Carling’s modification of the box plot (Carling, 2000) and Lenth method. If no outlier exists or there is a wide range in the inliers as determined by the Lenth method, more outliers can be found by the Carling method. A simulation study is conducted in unreplicated 24 designs with the number of active effects ranging from 1 to 6 to compare the efficiency of the Lenth method, original LGB methods, and the proposed modified version of the LGB method.  相似文献   
5.
The purpose of this study was to validate and expand on Y. B. Chung's (2001) models of work discrimination and coping strategies among lesbian, gay, and bisexual persons. In semistructured individual interviews, 17 lesbians and gay men reported 35 discrimination incidents and their related coping strategies. Responses were coded based on Chung's models. Results supported the validity of the Work Discrimination model and two coping strategy models (Vocational Choice and Identity Management). The Discrimination Management coping strategy model was expanded. Implications for practice and research are discussed.  相似文献   
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Kee H. Chung 《决策科学》1993,24(6):1215-1221
This paper presents a contingent-claims approach to project valuation when capital expenditures are made sequentially over time. It focuses on an important facet of sequential investment projects that the firm can undertake—or pass up projects—as more information becomes available. The contingent-claims approach takes account of this important feature of firms' investment decision process, whereas the traditional capital budgeting procedure does not. Since the traditional method does not reflect the options nature of investment opportunities, it underestimates the value of sequential investment projects. As a result, a naive implementation of the traditional capital budgeting procedure could result in rejecting profitable projects. The extent of undervaluation associated with the traditional capital budgeting procedure is greater when the correlation between the random component of the future asset value and that of the required capital expenditure is smaller and/or when the growth rate of the required capital expenditure is higher.  相似文献   
9.
This study examined the prevalence of workplace flexibility and the mechanisms that allow workplace flexibility to influence turnover intentions through work–family and family–work conflicts and job satisfaction among low‐wage workers in South Korea. Participants included 250 low‐wage workers whose monthly salary was less than 2 million Korean won (approx. $1,900). The study results indicate that low‐wage workers have limited access to workplace flexibility and that workplace flexibility plays a significant protective role in reducing their turnover intention, indirectly by decreasing work–family conflicts and enhancing job satisfaction. This article also discusses the implications of these findings for labor policy and social work practice.  相似文献   
10.
姜兰虹  徐荣崇 《南方人口》2001,16(3):6-15,5
本文针对悉尼和布里斯本两个都市之台湾移民的分布及居住迁徙作深入研究。主要透过深入访谈的方法 ,系统性的针对台湾移民选择居住地的因子及决策过程进行探讨 ,并尽量以社会地理学“局内人”的观点 ,架构居住地改变和选择的逻辑来思考整个迁徙过程的机制。研究结果显示 ,随着时间的改变 ,作迁徙决策时所考量的因子也会改变。刚到澳洲时 ,选择居住地的因子主要会考量亲友意见 ;随着经验的累积及对周遭环境的熟悉 ,个别差异性开始凸显 ,每个人对居住地的选择会有不同的考量与分析。在迁居上 ,有向双拼式建筑或都市公寓型房子搬迁的趋势  相似文献   
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