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61.
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Steven Martin 《Demography》2009,46(1):203-208
This analysis joins the debate on how declines in marriage have shifted the composition of the unmarried and married populations in the United States, and how compositional shifts have affected nonmarital birth rates. Gray, Stockard, and Stone (2006) presented one model for compositional effects that Ermisch (2009) challenged with alternative statistical tests. I propose an alternative model for compositional shifts based not on theory but on observed marriage and fertility patterns. The results from this alternative model are consistent with Ermisch’s findings yet support Gray et al.’s general case that compositional effects have had an important infiuence on nonmarital birth rates.  相似文献   
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A critical need exists to challenge approaches to nursing home care due to rigid organizational factors and hospital-like culture. It has been argued that resident care needs to move toward a person-centered approach by addressing the organizational, social, and physical environments in nursing home facilities, a process often known as culture change. In response to this need, the Centers for Medicare & Medicaid Services (CMS) has created funding for pay for performance (P4P) nursing home incentive programs to allow nursing home providers to receive CMS reimbursements for culture change in the facilities. Through care staff interviews, site observations, and a document review, this qualitative study assesses the impact of a Midwestern state P4P incentive program in three participating nursing homes. Using an environment and behavior (E-B) policy orientation framework, this study examines culture change through a focus on policy, the physical environment, place attachment, and social and psychological processes in the study settings.  相似文献   
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This study explores how online publics are engaging with organizations by creating and sharing brand-related content online, outside corporate-controlled communication environments. This research employs a quantitative content analysis of memes shared on the social networking site Imgur to reveal how user-generated content conveys meaning about organizations. The analysis reveals brand-centric memes are generally classified as orphan memes, or memes that have distinct textual and visual characteristics separating them from established or emerging meme families. Memes about organizations are neither an overwhelming reflection of biting criticism or support, but rather a reflection of online public engagement with organizations that primarily use humor and textual brand features (or quiddities) to convey their commitment and satisfaction with the organization and unite meme families.  相似文献   
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We consider two related aspects of the study of old‐age mortality. One is the estimation of a parameterized hazard function from grouped data, and the other is its possible deceleration at extreme old age owing to heterogeneity described by a mixture of distinct sub‐populations. The first is treated by half of a logistic transform, which is known to be free of discretization bias at older ages, and also preserves the increasing slope of the log hazard in the Gompertz case. It is assumed that data are available in the form published by official statistical agencies, that is, as aggregated frequencies in discrete time. Local polynomial modelling and weighted least squares are applied to cause‐of‐death mortality counts. The second, related, problem is to discover what conditions are necessary for population mortality to exhibit deceleration for a mixture of Gompertz sub‐populations. The general problem remains open but, in the case of three groups, we demonstrate that heterogeneity may be such that it is possible for a population to show decelerating mortality and then return to a Gompertz‐like increase at a later age. This implies that there are situations, depending on the extent of heterogeneity, in which there is at least one age interval in which the hazard function decreases before increasing again.  相似文献   
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The migration of political asylum seekers into the United States has long been a salient political topic; however, social scientists have yet to examine this process in its entirety and in the context of political changes since September 11, 2001. Previous research shows that humanitarian and strategic interests are important for decisions made by asylum officers but that research overlooks the decisions made by immigration judges. Here we examine decisions made by both asylum officers and immigration judges using data from a global set of countries, from 1999 to 2004. We find that the waning importance of human rights is more pronounced for asylum officers than for immigration judges after the attack on the World Trade Center. We also find that language heritage, specifically for asylum seekers from English‐, Spanish‐, and Arabic‐speaking countries, substantially affects acceptance rates made by both decision‐makers between the two time periods of our study.  相似文献   
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Urbanization and development are predicted to increase considerably in the United States over the next several decades, and this is expected to result in large-scale habitat loss, fragmentation and loss of wildlife species. Thus, natural parks and preserves are becomingly increasingly important in the conservation of regional biodiversity. We used mist-nets and AnabatII acoustic detectors to survey bats in 10 national parks in the southeastern U.S. and examined the relationship between bat community structure and development in the surrounding 5 km. We predicted that species richness would increase with park size and that species richness and evenness would decrease with development. Species richness was not related to development or any other landscape characteristics including park size. In contrast, species evenness declined with increasing development. Percent Developed land in the surrounding 5 km area was the only variable that entered into the stepwise regression model. The decrease in species evenness in the urban parks was due to the dominance of big brown bats (Eptesicus fuscus) in these parks. The percentage of big brown bats in our captures was positively related to percent Developed land in the surrounding area. Our data suggest that urban parks may be important for conserving regional bat biodiversity. However, the low species evenness in these parks suggests that some bat species may be susceptible to the effects of urbanization and may be extirpated over time. Thus, management of urban as well as rural parks should strive to conserve as much bat roosting and foraging habitat as possible.  相似文献   
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In drug development, it sometimes occurs that a new drug does not demonstrate effectiveness for the full study population but appears to be beneficial in a relevant subgroup. In case the subgroup of interest was not part of a confirmatory testing strategy, the inflation of the overall type I error is substantial and therefore such a subgroup analysis finding can only be seen as exploratory at best. To support such exploratory findings, an appropriate replication of the subgroup finding should be undertaken in a new trial. We should, however, be reasonably confident in the observed treatment effect size to be able to use this estimate in a replication trial in the subpopulation of interest. We were therefore interested in evaluating the bias of the estimate of the subgroup treatment effect, after selection based on significance for the subgroup in an overall “failed” trial. Different scenarios, involving continuous as well as dichotomous outcomes, were investigated via simulation studies. It is shown that the bias associated with subgroup findings in overall nonsignificant clinical trials is on average large and varies substantially across plausible scenarios. This renders the subgroup treatment estimate from the original trial of limited value to design the replication trial. An empirical Bayesian shrinkage method is suggested to minimize this overestimation. The proposed estimator appears to offer either a good or a conservative correction to the observed subgroup treatment effect hence provides a more reliable subgroup treatment effect estimate for adequate planning of future studies.  相似文献   
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