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701.
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   
702.
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   
703.
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   
704.
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   
705.
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   
706.
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   
707.
Adopting a spatio‐temporal lens, this article explores how highly qualified migrant women negotiate relationships and career motivations in specific socio‐structural contexts. Comparing migration experiences of Irish and Polish women in London, I explore similarities within and differences between these groups. Having joined the EU in 1973, Ireland can be regarded as part of “old EU”, while Poland joining in 2004 is part of the “new” wave of EU members. Migration from old and new member states is often discussed separately using different framing. This article contributes to understanding migration in three ways. Firstly, by developing comparative analysis, which goes beyond narrow and static migrant categories. Secondly, by challenging the temporary/transient versus permanence/integration dichotomy to explore a “sliding scale” of migrant trajectories. Thirdly, by illustrating how evolving relationships, through the life cycle, may enable but also hinder migrant women's opportunities for settling in or moving on.  相似文献   
708.
709.
The authors examined perceptions of key social cognitive career theory (Lent, Brown, & Hackett, 1994) variables related to college‐going and science, technology, engineering, math, and medical (STEMM) careers in 10th and 11th graders (N = 892) attending 3 rural Appalachian high schools. The authors examined differences in perceptions related to gender, prospective 1st‐generation college student status, and the presence or absence of aspirations to pursue a STEMM career. Young women and young men scored similarly on all but 1 dependent variable, college‐going self‐efficacy (young women scored higher). Students who had STEMM career aspirations had higher scores on every measure than those who did not. Results suggest examining a 3rd prospective 1st‐generation college student status group—students who are unsure of their parents’ education level—as a distinct group in future research. By examining the college‐going and STEMM attitudes of rural Appalachian high school students, this study advances the literature and informs practitioners on reducing educational and vocational inequalities in this region.  相似文献   
710.
The European Commission has been supporting a transition from a system of separate accounting to formula apportionment. After its 2011 draft directive was rejected by the Council, the Commission presented two new draft directives in October 2016, one stipulating rules for a common tax base and another the terms for consolidation and apportionment. The aspired system of unitary taxation is considered more resistant to profit shifting and assumed to reduce compliance costs. However, there are also doubts about the extent, to which such a system will eradicate tax-planning activities of MNEs. Other concerns have arisen about the practical issue of enforcing uniform rules for asset valuation throughout the member states. We use a dynamic model of tax accounting based on neoclassical investment theory and effective tax rates to determine to what extent formula apportionment mitigates the efficiency of typical profit-shifting strategies. We focus on the roles of transfer pricing and intragroup debt financing (through loans and leases) under both separate accounting and formula apportionment. We also take into account a possible leeway for inconsistent valuation. Our results show that instead of eliminating tax planning strategies, the proposed system might simply induce a shift from manipulating reported profits to influencing the apportionment key. Inside the European Union, the CCCTB may be able to render thin capitalisation rules and transfer pricing documentation redundant. However, formula apportionment invites for new forms of tax planning. It is therefore essential to give credit to these new kinds of tax incentives when implementing a system of unitary taxation.  相似文献   
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