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831.
We compared data drawn from a random sample of 399 current assisted living residents and a subsample of 222 newly admitted residents for two groups: childless residents and residents with children. The percentage of childless residents (26%) in our study was slightly higher than U.S. population estimates of childless individuals aged 65 years and older (20%). In the overall sample, the two groups differed significantly by age, race, and women's years of education. The childless group was slightly younger, had a higher percentage of African American residents, and had more years of education than the group with children. In the subsample, we looked at demographic, functional, financial, and social characteristics and found that childless residents reported fewer diagnoses of dementia and fewer visits from a relative but more reported paying less money per month for assisted living and having private insurance than residents with children. As childlessness among older adults continues to increase, it will become increasingly important to understand how child status affects the need for and experience of long-term care.  相似文献   
832.
Considered are stochastic continuous-time control systems described by stochastic differential equations, which are defined by special martingals. Examples are given by the well known Ito equations with respect to a Wiener - or a Poisson process. By means of a performance index, regarding current yields as well as a terminal payment a control problem is formulated. The essential result in view of concrete evaluation is the approximation by a sequence of discrete-time finite dimensional control problems.  相似文献   
833.
Abstract

We propose a cure rate survival model by assuming that the number of competing causes of the event of interest follows the negative binomial distribution and the time to the event of interest has the Birnbaum-Saunders distribution. Further, the new model includes as special cases some well-known cure rate models published recently. We consider a frequentist analysis for parameter estimation of the negative binomial Birnbaum-Saunders model with cure rate. Then, we derive the appropriate matrices for assessing local influence on the parameter estimates under different perturbation schemes. We illustrate the usefulness of the proposed model in the analysis of a real data set from the medical area.  相似文献   
834.
835.
This paper proposes a functional connectivity approach, inspired by brain imaging literature, to model cross-sectional dependence. Using a varying parameter framework, the model allows correlation patterns to arise from complex economic or social relations rather than being simply functions of economic or geographic distances between locations. It nests the conventional spatial and factor model approaches as special cases. A Bayesian Markov Chain Monte Carlo method implements this approach. A small scale Monte Carlo study is conducted to evaluate the performance of this approach in finite samples, which outperforms both a spatial model and a factor model. We apply the functional connectivity approach to estimate a hedonic housing price model for Paris using housing transactions over the period 1990–2003. It allows us to get more information about complex spatial connections and appears more suitable to capture the cross-sectional dependence than the conventional methods.  相似文献   
836.
We describe a first experiment on whether product complexity affects competition and consumers in retail markets. We are unable to detect a significant effect of product complexity on prices, except insofar as the demand elasticity for complex products is higher. However, there is qualified evidence that complex products have the potential to induce consumers to buy more than they would otherwise. In this sense, consumer exploitability in quantities cannot be ruled out. We also find evidence for shaping effects: consumers’ preferences are shaped by past experience with prices, and firms may in principle exploit this to sell more.  相似文献   
837.
A Diamond-Stiglitz approach to the demand for self-protection   总被引:1,自引:0,他引:1  
The existing research concerning the relationship between risk aversion and prudence and the demand for self-protection assumes that the loss variable follows a Bernoulli distribution, and that changes in the level of self-protection are mean preserving. The analysis here replaces these two very strong conditions with ones which are more general. When doing this, the method of analysis is also significantly modified. This modification includes representing a change in the level of self-protection using the procedure developed by Diamond and Stiglitz (Journal of Economic Theory 8:337-360, 1974) for representing a change in risk. This alternate representation allows the existing findings to be generalized considerably, and also simplifies the analysis.  相似文献   
838.
Despite the fact that sickle-cell disease (SCD) is perhaps the most “racialized” medical condition in the USA, very little is known about how “race” impacts public support for health policies related to the condition. We embedded an experiment within the 2011 Cooperative Congressional Election Study in order to assess perceptions about SCD among 1250 participants from diverse backgrounds and evaluate the extent to which these perceptions were associated with support for government spending on SCD-related benefits. We manipulated the racial phenotype of SCD advocates who requested additional government funding and asked participants to indicate how much the government should provide. Overall, participants expressed moderately positive attitudes about SCD, and there were no differences in funding support based on the race of the advocate. However, white participants supported less funding compared to nonwhite participants, even after adjusting for a number of demographic and attitudinal covariates. These findings suggest that a complex relationship between racial identification and implicit racism may shape public perceptions about SCD that negatively influences perceivers’ support for SCD-related policy.  相似文献   
839.
This study examined reciprocal support networks involving extended family, friends and church members among African Americans. Our analysis examined specific patterns of reciprocal support (i.e., received only, gave only, both gave and received, neither gave or received), as well as network characteristics (i.e., contact and subjective closeness) as correlates of reciprocal support. The analysis is based on the African American subsample of the National Survey of American Life. Overall, our findings indicate that African Americans are very involved in reciprocal support networks with their extended family, friends and church members. Respondents were most extensively involved in reciprocal supports with extended family members, followed closely by friends and church networks. Network characteristics (i.e., contact and subjective closeness) were significantly and consistently associated with involvement with reciprocal support exchanges for all three networks. These and other findings are discussed in detail. This study complements previous work on the complementary roles of family, friend and congregational support networks, as well as studies of racial differences in informal support networks.  相似文献   
840.
This study explored the extent to which private regard and religiosity beliefs serve as protective factors for school bonding among African American and Caribbean black adolescents who experience racial discrimination in school. Findings are drawn from a nationally representative sample of (n = 810) African American and (n = 360) Caribbean black adolescents (52% girls) aged 13–17 (Mage = 15, SD = 1.42) years. Results suggest that perceiving racial discrimination from teachers was associated with lower levels of school bonding for African American and Caribbean black adolescents. For African American adolescents, perceiving more racial discrimination from teachers and reporting lower private regard beliefs was associated with less school bonding. The findings for Caribbean black adolescents revealed that endorsing moderate levels of religiosity and perceiving higher rates of teacher discrimination was associated with less school bonding. The developmental significance and implications for future research are discussed.  相似文献   
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