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731.
732.
We analyze a class of linear regression models including interactions of endogenous regressors and exogenous covariates. We show how to generate instrumental variables using the nonlinear functional form of the structural equation when traditional excluded instruments are unknown. We propose to use these instruments with identification robust IV inference. We furthermore show that, whenever functional form identification is not valid, the ordinary least squares (OLS) estimator of the coefficient of the interaction term is consistent and standard OLS inference applies. Using our alternative empirical methods we confirm recent empirical findings on the nonlinear causal relation between financial development and economic growth. 相似文献
733.
An often-cited fact regarding mixing or mixture distributions is that their density functions are able to approximate the density function of any unknown distribution to arbitrary degrees of accuracy, provided that the mixing or mixture distribution is sufficiently complex. This fact is often not made concrete. We investigate and review theorems that provide approximation bounds for mixing distributions. Connections between the approximation bounds of mixing distributions and estimation bounds for the maximum likelihood estimator of finite mixtures of location-scale distributions are reviewed. 相似文献
734.
Lifetime Data Analysis - This work was motivated by observational studies in pregnancy with spontaneous abortion (SAB) as outcome. Clearly some women experience the SAB event but the rest do not.... 相似文献
735.
Max Döring 《Journal of Statistical Computation and Simulation》2019,89(16):2997-3034
The aim of this article is to review existing goodness-of-fit tests for the exponential distribution under progressive Type-II censoring and to provide some new ideas and adjustments. In particular, we consider two-parameter exponentially distributed random variables and adapt the proposed test procedures to our scenario if necessary. Then, we compare their power by an extensive simulation study. Furthermore, we propose five new test procedures that provide reasonable alternatives to those already known. 相似文献
736.
Sarah D. Holmes Elizabeth Galik Barbara Resnick 《Journal of Housing for the Elderly》2019,33(1):56-71
This study examined whether residents' level of resilience mediated the relationship between social support for exercise from staff and resident satisfaction in assisted living. This was a secondary data analysis using baseline data from a function-focused care intervention study including 171 residents from four assisted living facilities. Using structural equation modeling, we found that mood and social support for exercise from staff were the only variables associated with resilience. Mood, gender, cognition, and social support for exercise from staff directly influenced resident satisfaction and explained 31% of the variance in the model. Implications for future research and practice are discussed. 相似文献
737.
David Luther Albright Kate Hendricks Thomas Justin McDaniel Kari Lynne Fletcher Kelli Godfrey Jessica Bertram 《Journal of American college health : J of ACH》2019,67(5):479-485
Objective: The purpose of this study was to assess the current state of postsecondary educational settings’ outreach to military women who become students postservice. Participants: Data for the present cross-sectional study were obtained from the American College Health Association’s (ACHA) 2011–2014 National College Health Assessment II (NCHA). Methods: Demographic characteristics of the study sample were explored by calculating frequencies and percentages by military service status. Research questions were explored with Fisher’s exact test, maximum likelihood multiple logistic regression, as appropriate. Results: Women service member and veteran students received health information from their university/college less often than women students with no military experience on the following topics: alcohol and other drug use, depression and anxiety, sexual assault and relationship violence prevention, and stress reduction. Conclusions: The findings of this research identified clear gaps in service provision for women student veterans on college campuses and provided some possible models for intervention development. 相似文献
738.
Michael Mackert Kathleen Case Allison Lazard Jeeyun Oh Jessica Hughes Wagner Ernest Hawk 《Journal of American college health : J of ACH》2019,67(4):291-298
Objective: Despite declining cigarette smoking rates in the US, there is a continued need for tobacco prevention education campaigns to reach young adults. Recognizing the need for improved tobacco control messaging, the University of Texas (UT) System engaged The University of Texas at Austin Center for Health Communication to develop a brand and message that would strengthen tobacco control efforts at its 14 institutions. Methods: This article describes the iterative process involved in creating a brand for tobacco control, including an environmental scan, identifying potential message themes, and creating and refining logos. Results: This article highlights the process of developing a system-wide tobacco control brand. Specifically, the process included coordinating an interdisciplinary team with content and design experts, and presenting ideas to stakeholders for serial feedback and refinement, among others. Conclusions: Ultimately, this project offers a model for other systems of higher education interested in pursuing similar initiatives. 相似文献
739.
This article introduces the concept of the interloper for examining classed and gendered dislocation. Focusing on academia, which we view as a classed and gendered field, we draw on Bourdieu and feminist standpoint theory to account for how we, as women of working‐class origin, have experienced ‘breaches' through which we have come to understand ourselves in classed and gendered terms. Coming from different cultural backgrounds, we also reflect on how understandings of class are context‐specific. We employ a duoethnographic method which emphasizes the value of subjective experiences for organizational and social analyses. The article shows how the concept of the interloper may shed light on the dynamic, relational character of constructions of class and gender; the maintenance work that is performed; and how a sense of permanent inbetweenness characterizes our ongoing movement between the fields of the family and academia. 相似文献
740.
D. C. Wickramarachchi B. L. Robertson M. Reale C. J. Price J. A. Brown 《Australian & New Zealand Journal of Statistics》2019,61(3):380-391
We present an algorithm for learning oblique decision trees, called HHCART(G). Our decision tree combines learning concepts from two classification trees, HHCART and Geometric Decision Tree (GDT). HHCART(G) is a simplified HHCART algorithm that uses linear structure in the training examples, captured by a modified GDT angle bisector, to define splitting directions. At each node, we reflect the training examples with respect to the modified angle bisector to align this linear structure with the coordinate axes. Searching axis parallel splits in this reflected feature space provides an efficient and effective way of finding oblique splits in the original feature space. Our method is much simpler than HHCART because it only considers one reflected feature space for node splitting. HHCART considers multiple reflected feature spaces for node splitting making it more computationally intensive to build. Experimental results show that HHCART(G) is an effective classifier, producing compact trees with similar or better results than several other decision trees, including GDT and HHCART trees. 相似文献