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81.
82.
Children in the child welfare system are dependent upon Medicaid to finance services for their considerable mental health needs. This study examines the effects of Medicaid policies on mental health service use among a national probability sample of children in the child welfare system. Data for this study came from the National Survey of Child and Adolescent Well-Being, the Caring for Children in Child Welfare study, and the Area Resource File. Weighted multivariate logistic regression analyses were conducted to estimate effects of policy variables on children's use of mental health services, controlling for child-level covariates and county-level health resources. Children in counties with behavioral carve-outs under Medicaid managed care had lower odds of inpatient mental health service use. Medicaid managed care enrollment and variations in type of provider reimbursement did not affect use of mental health services. Older age, greater need for mental health services, and higher levels of caregiver education were associated with increased odds of service use. Restrictions on use of inpatient mental healthcare caused by behavioral carve-outs may disproportionately affect children in the child welfare system who have high rates of such use. Careful adoption of carve-outs is necessary to assure appropriate care for these children.  相似文献   
83.
This paper documents and analyzes how landholders managed to uplift status of their neighborhood from hazard land as designated by the 1978 master plan to a regularized residential settlement through land regularization in Dar es Salaam city. Specifically, explores policy framework governing land regularization and how the local community explored the opportunities it offers. Documents the local community planning and land regularization processes undertaken focusing on land use planning, drainage construction, and cadastral survey and discuses how financial resources were raised, trust was built as well as factors which sustained community involvement towards meeting their interests of securing tenure. The paper also, draws challenges facing land regularization policy and recommends areas for further interventions commensurate with the human dimension challenges in securing tenure.Underlying community involvement, those aspects of community, which have been connected to the idea of social capital namely existence of committed leadership in land development matters, embracing mechanism for participatory decision making process and educational background to local leaders were particularly important in determining success for the case. Others include economic ability to contribute, high proportion of landholder settlers, land conflict task force formulation, local consensus to solve commonly felt problems, existence of strong community organization, and unwritten norms put in place to regulate individual behavior in building construction. Weak legal recognition of informal settlement, lengthy and bureaucratic procedures in planning and approval of regularization plans, weak knowledge on land management matters, short-term title deeds with low financial betterments, political popularity are identified critical challenges.Some of recommendations put forward include formalization of the grass-roots role in decision-making, decentralizing some of land development control functions to sub-ward leaders and training the same in basic land management matters. Others include definition of norms; by-laws and government facilitation of informal land parceling. Besides community support should be sought so as to create partnership in the promotion of security of tenure in informal areas. The study concludes that, unless land development activities ongoing in informal settlements are closely monitored and regulated as the settlement grow, it will be too costly socially and economically to retrofit once the settlement have identified.  相似文献   
84.
Proportional reversed hazard rate model and its applications   总被引:1,自引:0,他引:1  
The purpose of this paper is to study the structure and properties of the proportional reversed hazard rate model (PRHRM) in contrast to the celebrated proportional hazard model (PHM). The monotonicity of the hazard rate and the reversed hazard rate of the model is investigated. Some criteria of aging are presented and the inheritance of the aging notions (of the base distribution) by the PRHRM is studied. Characterizations of the model involving Fisher information are presented and the statistical inference of the parameters is discussed. Finally, it is shown that several members of the proportional reversed hazard rate class have been found to be useful and flexible in real data analysis.  相似文献   
85.
86.
To capture mean and variance asymmetries and time‐varying volatility in financial time series, we generalize the threshold stochastic volatility (THSV) model and incorporate a heavy‐tailed error distribution. Unlike existing stochastic volatility models, this model simultaneously accounts for uncertainty in the unobserved threshold value and in the time‐delay parameter. Self‐exciting and exogenous threshold variables are considered to investigate the impact of a number of market news variables on volatility changes. Adopting a Bayesian approach, we use Markov chain Monte Carlo methods to estimate all unknown parameters and latent variables. A simulation experiment demonstrates good estimation performance for reasonable sample sizes. In a study of two international financial market indices, we consider two variants of the generalized THSV model, with US market news as the threshold variable. Finally, we compare models using Bayesian forecasting in a value‐at‐risk (VaR) study. The results show that our proposed model can generate more accurate VaR forecasts than can standard models.  相似文献   
87.
Summary. The paper develops methods for the design of experiments for mechanistic models when the response must be transformed to achieve symmetry and constant variance. The power transformation that is used is partially justified by a rule in analytical chemistry. Because of the nature of the relationship between the response and the mechanistic model, it is necessary to transform both sides of the model. Expressions are given for the parameter sensitivities in the transformed model and examples are given of optimum designs, not only for single-response models, but also for experiments in which multivariate responses are measured and for experiments in which the model is defined by a set of differential equations which cannot be solved analytically. The extension to designs for checking models is discussed.  相似文献   
88.
We examine how attention to animacy information may contribute to children's developing knowledge of language. This research extends beyond prior research in that children were shown dynamic events with novel entities, and were asked not only to comprehend sentences but to use sentence structure to infer the meaning of a new word. In a 4 × 3 design, animacy status (e.g., animate agent, inanimate patient) and labeling syntax (agent, patient, nonlabel control) were varied. Across most events, 2 1/2‐year‐old participants responded as if they expected animate entities to be named. However, in a prototypical (animate agent‐inanimate patient) event condition, children responded differentially across different syntactic structures. Thus, the clearest evidence for attention to syntactic cues was found in the prototypical event condition. These results suggest that young children attend to the animacy status of unfamiliar entities, that they have expectations about animacy relations in events, and that these expectations support emerging syntactic knowledge.  相似文献   
89.
Abstract. The use of the concept of ‘direct’ versus ‘indirect’ causal effects is common, not only in statistics but also in many areas of social and economic sciences. The related terms of ‘biomarkers’ and ‘surrogates’ are common in pharmacological and biomedical sciences. Sometimes this concept is represented by graphical displays of various kinds. The view here is that there is a great deal of imprecise discussion surrounding this topic and, moreover, that the most straightforward way to clarify the situation is by using potential outcomes to define causal effects. In particular, I suggest that the use of principal stratification is key to understanding the meaning of direct and indirect causal effects. A current study of anthrax vaccine will be used to illustrate ideas.  相似文献   
90.
The paradigm in disability supports is shifting away from institutional services and professional control towards self-determination and community involvement of people with disabilities. The assumption that the best way to provide disability supports is for government to give money to agencies or services, rather than directly to people with disabilities and their support networks, is being challenged. This article reports on findings and themes from a Canadian study that investigated individualised funding projects from different parts of the world. Ten of fifteen of the most 'promising initiatives' were selected for more detailed study and analysis. Projects analysed were from Canada, the US, and Australia. Themes emerging from the study included the fact that values and principles mattered, a policy framework provided coherence and equity, infrastructure supports for individuals were separate from service system, the facilitator-broker role differed from case management, allocation of individualised funds was designed to be equitable and account able to the funder and person, and a 'learn as you go' philosophy maximised positive outcomes. This research project demonstrates that individualised support and funding, when embedded in the new paradigm of disability and community, builds capacity of individuals, families, and communities.  相似文献   
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