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831.
Carlos J. Pérez-González Arturo J. Fernández 《Journal of Statistical Computation and Simulation》2019,89(13):2489-2504
An accurate procedure is proposed to calculate approximate moments of progressive order statistics in the context of statistical inference for lifetime models. The study analyses the performance of power series expansion to approximate the moments for location and scale distributions with high precision and smaller deviations with respect to the exact values. A comparative analysis between exact and approximate methods is shown using some tables and figures. The different approximations are applied in two situations. First, we consider the problem of computing the large sample variance–covariance matrix of maximum likelihood estimators. We also use the approximations to obtain progressively censored sampling plans for log-normal distributed data. These problems illustrate that the presented procedure is highly useful to compute the moments with precision for numerous censoring patterns and, in many cases, is the only valid method because the exact calculation may not be applicable. 相似文献
832.
Adam J. Saffer 《Public Relations Review》2019,45(2):282-296
Scholars have theorized that public relations contributes to societies and communities by bringing attention to pressing public issues and fostering social capital in civil society networks. However, the extant research has studied civil society networks of NGOs, donors, and the media in transitional countries. This study extends the public relations model of civil society in two ways. First, it broadens the scope to an international context. Second, it draws from the multi-stakeholder issue network perspective to conceptualize a civil society network as a space where stakeholders of an issue mix their interests as they collectively address a pressing public issue. The literature on international and multi-stakeholder networks suggest that the international scope and the mixing of interests across sectors may restrict the production of social capital. The results from the social network analysis suggests that the mixing of interests across sectoral and geopolitical boundaries did not restrict the production of social capital. Rather, the patterns of the relationships among those on the core and those on the periphery of the network restricted the production of social capital. Such finding demonstrates how public relations’ functions like relationship building can have profound influences on social capital and civil society networks. The implications for public relations theorizing and research are discussed. 相似文献
833.
Jennifer M. Cadigan Emily R. Dworkin Jason J. Ramirez Christine M. Lee 《Journal of American college health : J of ACH》2019,67(4):383-390
Objective: The objective of this study was to understand substance use patterns of alcohol, marijuana, and simultaneous alcohol and marijuana (SAM) use among 2- and 4-year college students. Participants: Participants were 526 young adults aged 18–23 (n?=?355 4-year students; n?=?171 2-year students) recruited from February 2015 to January 2016 who were participating in a larger longitudinal study. Methods: Latent class analysis (LCA) was used to identify past-month classes of alcohol, marijuana, and SAM use. Results: Among both 2- and 4-year students, a four-class solution yielded the best-fitting model, with 2-year classes tending to include greater marijuana use and less alcohol use and 4-year classes tending to include heavy alcohol use. Demographic characteristics were largely similar across classes. Conclusions: Classes of alcohol, marijuana, and SAM use differed by education status. Screening and prevention efforts for 4-year students may need to be tailored for the needs of 2-year students. 相似文献
834.
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
835.
We conduct an experiment that examines the relationship between girls only schooling and risk taking and competitive behavior. In it, we compare decisions made by students in an all‐girls' school to those made by students in a closely matched coeducational school. We further investigate the developmental nature of this behavior by comparing choices made by younger students (Grades 7 and 8) with those of older students (Grades 11 and 12). We focus on the differences between those who select into the all‐girls' school, and find that although girls educated in a single sex environment are the most risk averse, they are also among the most competitive. These results lend texture to the hypothesis that “nurture matters” in the gender differences debate. (JEL C93, J16, I21) 相似文献
836.
Adult Protective Services (APS) professionals are often called on to assess decision-making capacity when investigating financial exploitation. Previous research found that in consecutive APS cases, a decision-making screening scale (LFDSS) also detected financial exploitation. The purpose of this study was to apply the clinical cutoff scores derived from the previous study to a new sample of APS cases. Using a sample of 105 participants, from APS workers across 5 counties this study investigated the clinical utility of the LFDSS to detect financial exploitation based on ratings by APS professionals using the scale. Results demonstrate that the LFDSS has excellent internal consistency and clinical utility properties. This paper provides support for use of the LFDSS as a reliable and valid instrument. Instructions for use of the LFDSS are included in the article, along with information about online support tools. 相似文献
837.
Peter McDonald Helen Moyle Jeromey Temple 《The Australian journal of social issues》2019,54(2):112-134
Using Australian census data, the paper examines the incidence of poor English competency in Australia from 1981 onwards. The paper examines English competency in relation to various characteristics such as sex, age, language spoken, visa type, citizenship, duration of residence and location. It finds that there was a sharp rise in the numbers of people not speaking English well between the 2011 and 2016 Censuses and special attention is given to this rise in the paper. Recently, the Australian Government unsuccessfully legislated for the introduction of a requirement of English competency at the level of IELTS 6 (the commonly used university entrance level) as a condition for the award of Australian citizenship. The paper argues that this test would have led to a very large number of disenfranchised Australian permanent residents and this would be a highly undesirable result. Nevertheless, employment and social participation are strongly influenced by English competency and residents with poor English are disadvantaged. The policy suggestion is made that participation in a course of English language training for those without functional English skills could be made a precondition of the award of permanent residence—without the application of a passing grade. 相似文献
838.
Many central banks set inflation targets over the medium term and inflation projections are a key input for monetary policy decision making. In this paper, we present the procedures used by the Spanish Central Bank staff to project consumer price inflation. We also provide some illustrations of their policy uses, such as fan charts, deflation probabilities and the monitoring of inflation targets. 相似文献
839.
Bleichrodt Han Doctor Jason N. Gao Yu Li Chen Meeker Daniella Wakker Peter P. 《Journal of Risk and Uncertainty》2019,59(3):239-260
We present a theoretical model of Rabin’s famous calibration paradox that resolves confusions in the literature and that makes it possible to identify the causes of the paradox. Using suitable experimental stimuli, we show that the paradox truly violates expected utility and that it is caused by reference dependence. Rabin already showed that utility curvature alone cannot explain his paradox. We, more strongly, do not find any contribution of utility curvature to the explanation of the paradox. We find no contribution of probability weighting either. We conclude that Rabin’s paradox underscores the importance of reference dependence.
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