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961.
Linear mixed models have been widely used to analyze repeated measures data which arise in many studies. In most applications, it is assumed that both the random effects and the within-subjects errors are normally distributed. This can be extremely restrictive, obscuring important features of within-and among-subject variations. Here, quantile regression in the Bayesian framework for the linear mixed models is described to carry out the robust inferences. We also relax the normality assumption for the random effects by using a multivariate skew-normal distribution, which includes the normal ones as a special case and provides robust estimation in the linear mixed models. For posterior inference, we propose a Gibbs sampling algorithm based on a mixture representation of the asymmetric Laplace distribution and multivariate skew-normal distribution. The procedures are demonstrated by both simulated and real data examples. 相似文献
962.
In this article we discuss various strategies for constructing bivariate Kumaraswamy distributions. As alternatives to the Nadarajah et al. (2011) bivariate model, four different models are introduced utilizing a conditional specification approach, a conditional survival function approach, and an Arnold–Ng bivariate beta distribution construction approach. Distributional properties for such bivariate distributions are investigated. Parameter estimation strategies for the models are discussed, as are the consequences of fitting two of the models to a particular data set involving the proportion of foggy days at two different airports in Colombia. 相似文献
963.
964.
Bráulio M. Veloso Thais R. Correa Marcos O. Prates Gabriel F. Oliveira Andréa I. Tavares 《Statistics and Computing》2017,27(4):1099-1110
Crime or disease surveillance commonly rely in space-time clustering methods to identify emerging patterns. The goal is to detect spatial-temporal clusters as soon as possible after its occurrence and to control the rate of false alarms. With this in mind, a spatio-temporal multiple cluster detection method was developed as an extension of a previous proposal based on a spatial version of the Shiryaev–Roberts statistic. Besides the capability of multiple cluster detection, the method have less input parameter than the previous proposal making its use more intuitive to practitioners. To evaluate the new methodology a simulation study is performed in several scenarios and enlighten many advantages of the proposed method. Finally, we present a case study to a crime data-set in Belo Horizonte, Brazil. 相似文献
965.
采用2007—2014年中国沪深两市A股上市公司数据,研究行业特征和盈利能力对上市公司盈余管理水平的影响,实证分析结果表明:农业上市公司较非农上市公司具有更高的应计盈余管理水平和真实盈余管理水平;上市公司的盈利能力与应计盈余管理水平正相关,而与真实盈余管理水平负相关;较高的盈利能力强化了行业特征对真实盈余管理水平的正向影响,而对应计盈余管理水平则不具有这种影响。该研究不仅证实了农业上市公司较非农上市公司实施了更为严重的盈余操控,还揭示出上市公司的盈利能力对应计盈余管理水平和真实盈余管理水平的影响存在异质性以及盈利能力对行业特征与两种盈余管理水平之间关系的调节作用也存在异质性。 相似文献
966.
967.
Jennifer M. Geiger Justine R. Cheung Jeanne E. Hanrahan Cynthia A. Lietz Breanna M. Carpenter 《Journal of social service research》2017,43(5):566-579
Research shows that few foster care alumni enroll and complete post-secondary education. For those who do enroll, many experience challenges associated with academic and social adjustment and are at risk of dropping out. Many college-based programs are being developed and are available to foster care alumni to support them during their post-secondary education. This study used pre-tests, post-tests, and journal entries of seventeen participants to evaluate a strengths-based, resilience-oriented early-start program for newly enrolled students at a large public university that provides knowledge about the institution, resources (e.g., tutoring), and social support necessary for foster care alumni to make a smooth transition into college life and to increase short and long-term student success. Quantitative and qualitative findings indicate that students who participated in the early-start program showed increased confidence and competency in academic and social adjustment. Findings also showed personal growth (e.g., building resiliency) and an increased connectedness among students who participated in the program. Study findings can inform the development of new on-campus support programs and help enhance existing programming. Future research should address short and long-term outcomes and experiences of students who are former foster youth who have participated in on-campus support programs. 相似文献
968.
ABSTRACTThis study describes a community-university partnership to support a gerontological social work student-delivered respite program, the Houseguest Program (Houseguest). Houseguest was designed using a community-engaged scholarship model of integrating research, teaching, and service. Houseguest was piloted with a small group of community-dwelling, coresiding dementia caregivers and care recipients. We examined caregivers’ experiences with student-delivered respite using qualitative data analysis. Thematic analysis produced 8 themes: (a) respite from full time caregiving role, (b) information on caregiving strategies, (c) no-cost supportive services, (d) opportunity for care recipients to socialize, (e) tailored activities for care recipients, (f) rapport-building between students and family dyad, (g) reciprocity between students and family dyad, and (h) program continuation. We conclude with a proposed community-engaged scholarship model for dementia caregiving. Through a community-university partnership, Houseguest reduced the impact of caregiver burden and created an opportunity for students to serve families affected by dementia through respite and tailored activities. 相似文献
969.
Dexter R. Voisin Dongha Kim Lois Takahashi Phillip Morotta Kathryn Bocanegra 《Journal of social service research》2017,43(1):129-140
While researchers have found that African American youth experience higher levels of juvenile justice involvement at every system level (arrest, sentencing, and incarceration) relative to their other ethnic counterparts, few studies have explored how juvenile justice involvement and number of contacts might be correlated with this broad range of problems. A convenience sample of 638 African American adolescents living in predominantly low-income, urban communities participated in a survey related to juvenile justice involvement. Major findings using logistic regression models indicated that adolescents who reported juvenile justice system involvement versus no involvement were 2.3 times as likely to report mental health problems, substance abuse, and delinquent or youth offending behaviors. Additional findings documented that the higher the number of juvenile justice system contacts, the higher the rates of delinquent behaviors, alcohol and marijuana use, sex while high on drugs, and commercial sex. These findings suggest that identifying and targeting youth who have multiple juvenile justice system contacts, especially those in low-resourced communities for early intervention services, may be beneficial. Future research should examine whether peer network norms might mediate the relationships between juvenile justice involvement and youth problem behaviors. 相似文献
970.
Agreement and discrepancy between children,parents, and social workers on school‐based effort avoidance in child welfare services
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Hanna Maria Weber Franz Petermann Stefan Rücker Peter Büttner 《Child & Family Social Work》2017,22(4):1431-1439
A multiperspective approach is beneficial for obtaining reliable and multifaceted pictures of child behaviour problems. The goal of the present study is to examine interrater agreement on school‐based effort avoidance between children receiving child welfare services, parents, and social workers. Given previous findings, interrater agreement is expected to be low. Self‐reported data on school‐based effort avoidance were gathered for children and adolescents in child welfare services. Additionally, social workers (using the Teacher‐Report Checklist for social and learning behaviour) and parents (using the parallel version of the self‐rating questionnaire on school‐based effort avoidance) were asked to complete an external assessment tool to compare children's perspectives with the ratings of significant adults. The results confirmed significant discrepancies between parents' and children's ratings on effort avoidance tendencies. Furthermore, there were only small to moderate correlations between children's self‐ratings and the adults' assessments; however, the consensus between adults was higher than the interrater agreement between children and social workers. Discrepancies in ratings from multiple informants underline the importance of integrating multiple perspectives, especially children's perspectives, in the diagnostic process in order to plan and adapt appropriate care and treatment. 相似文献