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41.
Conventional advice is to reduce risky investments as one ages. Such a generalized focus on risk avoidance may be inappropriate for elderly with longer life spans and those with financial goals that extend beyond their lifetime. To better understand risky asset holdings among the elderly, we investigated the effect of cognitive ability and bequest motive on stock ownership and stock purchase. Using the 2004 wave of the Health and Retirement Study, we found that one-third of elderly households held stocks and 36% of those elderly stockowners had recently acquired stocks. The respondent??s cognitive ability and bequest motive were strongly related to stock ownership. Among those who owned stock, a bequest motive was positively related to a recent purchase of stocks.  相似文献   
42.
Social Indicators Research - As the “weak-institutions trap” is increasingly recognized as the major hindrance to growth, the advantages offered by e-government may provide an...  相似文献   
43.
It is often the case that high-dimensional data consist of only a few informative components. Standard statistical modeling and estimation in such a situation is prone to inaccuracies due to overfitting, unless regularization methods are practiced. In the context of classification, we propose a class of regularization methods through shrinkage estimators. The shrinkage is based on variable selection coupled with conditional maximum likelihood. Using Stein's unbiased estimator of the risk, we derive an estimator for the optimal shrinkage method within a certain class. A comparison of the optimal shrinkage methods in a classification context, with the optimal shrinkage method when estimating a mean vector under a squared loss, is given. The latter problem is extensively studied, but it seems that the results of those studies are not completely relevant for classification. We demonstrate and examine our method on simulated data and compare it to feature annealed independence rule and Fisher's rule.  相似文献   
44.
ABSTRACT

Guided by the Person-Environment Fit perspective, we investigated the extent to which personal and environmental factors influence depression among community-dwelling adults. The data came from the special section about community-based service utilization in the 2012 Health and Retirement Study (N=1,710). Although community-based service was not significantly associated with depression after controlling for covariates, respondents with functional limitations and living alone were less likely to be depressed when using community-based services. This study demonstrates the different associations between community-based services and depression depending on personal needs. It discusses the importance of community-based services for aging-in-place policy, particularly among vulnerable populations.  相似文献   
45.
The purpose of this study was to explore the relationship between job engagement and two key components of employee-organization relationships (EOR). Findings from a survey of members of the Millennial Generation (N = 539) in the United States indicate that job engagement mediates the relationship between employee communication and organizational commitment. It is concluded that when employees are engaged in their work, their commitment to the organization is strengthened and the likelihood of them leaving the organization decreases. Furthermore, an argument is made in light of the study’s findings that engagement and commitment work in concert to strengthen EORs overall. To foster engagement, organizations should remove obstacles to internal information flow and provide ongoing feedback to employees about individual and organizational issues.  相似文献   
46.
Robust parameter designs (RPDs) enable the experimenter to discover how to modify the design of the product to minimize the effect due to variation from noise sources. The aim of this article is to show how this amount of work can be reduced under modified central composite design (MCCD). We propose a measure of extended scaled prediction variance (ESPV) for evaluation of RPDs on MCCD. Using these measures, we show that we can check the error or bias associated with estimating the model parameters and suggest the values of α recommended for MCCS under minimum ESPV.  相似文献   
47.
48.
While the association between financial strain and couple interaction has been well-established in the literature on economic stress, little research has investigated the association among middle-aged and older populations. The present study examined the relationships between financial strain and couple functioning of middle-aged, young-old, and old–old people using the 2010 Health and Retirement Study. Findings show that subjective financial strain was positively associated with partner undermining and negatively with partner support, controlling for the effects of objective financial situations among middle-aged, young-old, and old–old couples. There were gender and age differences in the interaction effects of financial strain and financial control on couple functioning. For middle-aged men, financial control may have different associations with couple behaviors depending on the level of financial strain. When the level of financial strain is high, the positive effect of financial control disappears and the effect changes even in a negative way. Findings provide suggestions for practitioners and researchers.  相似文献   
49.
This article discusses regression analysis of multivariate panel count data in which the observation process may contain relevant information about or be related to the underlying recurrent event processes of interest. Such data occur if a recurrent event study involves several related types of recurrent events and the observation scheme or process may be subject-specific. For the problem, a class of semiparametric transformation models is presented, which provides a great flexibility for modelling the effects of covariates on the recurrent event processes. For estimation of regression parameters, an estimating equation-based inference procedure is developed and the asymptotic properties of the resulting estimates are established. Also the proposed approach is evaluated by simulation studies and applied to the data arising from a skin cancer chemoprevention trial.  相似文献   
50.
In this paper, we show that a hypergeometric random variable can be represented as a sum of independent Bernoulli random variables that are, except in degenerate cases, not identically distributed. In the proof, we use the factorial moment generating function. An asymptotic result on the probabilities of the Bernoulli random variables in the sum is also presented. Numerical examples are used to illustrate the results.  相似文献   
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