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261.
Statistics and Computing - In this paper, we develop a very efficient approach to the Monte Carlo estimation of the expected value of partial perfect information (EVPPI) that measures the average... 相似文献
262.
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
263.
Rebecca L. C. Taylor Scott Kaplan Sofia B. Villas‐Boas Kevin Jung 《Economic inquiry》2019,57(3):1480-1496
We examine how soda sales changed due to the campaign attention and election outcome of a local excise tax on sugar‐sweetened beverages. Using panel data of beverage sales from university retailers in Berkeley, California, we estimate that soda purchases relative to control beverages significantly dropped immediately after the election, months before the tax was implemented in the city of Berkeley or on campus. Supplemental scanner data from off‐campus retailers reveal this result is not unique to the university setting. Our findings suggest soda tax media coverage and election outcomes can have larger effects on purchasing behavior than the tax itself. (JEL D12, H20, C23, I38, Q18) 相似文献
264.
Jennifer J. Lambert‐Shute Hoa N. Nguyen Paul W. Peterson Annisa B. Pirasteh 《Journal of marital and family therapy》2019,45(2):256-274
In this content analysis, researchers examine articles published from 2000 to 2015 in three family therapy journals, yielding a total of 948 empirical articles. The purpose is to provide an overview of the research being published, assess who is publishing, and investigate the current state of clinical effectiveness research in marriage and family therapy (MFT). Most first authors were affiliated with MFT programs and primarily included diversity and couples in their research. There was a significant increase of research on clinical process—though the number of clinical outcome studies held steady. There were no significant changes with regard to research funding. Implications support the use of innovative research methods to provide evidence of clinical effectiveness. 相似文献
265.
Putman Breanna J. Gasca Maria Blumstein Daniel T. Pauly Gregory B. 《Urban Ecosystems》2019,22(6):1071-1081
Urban Ecosystems - Urbanization-induced habitat loss and alteration causes significant challenges for the survival of many species. Identifying how species respond to urbanization can yield... 相似文献
266.
Aguilera Guillermo Ekroos Johan Persson Anna S. Pettersson Lars B. Öckinger Erik 《Urban Ecosystems》2019,22(2):335-344
Urban Ecosystems - Loss and fragmentation of semi-natural grasslands have had negative consequences for grassland biodiversity, such as butterflies. Urban parks and other urban green spaces have so... 相似文献
267.
Poutasi W. B. Urale Michael A. O'Brien 《Kōtuitui : New Zealand Journal of Social Sciences Online》2019,14(1):80-94
While there is a global shift towards smaller families, some groups maintain relatively high fertility rates. The 2013 New Zealand census data were used to investigate the nature of fertility between ethnicities in New Zealand. The NZ Deprivation Index 2013 was used as a measure of socioeconomic status to determine the relationships with fertility. The results mirror research outside of New Zealand in that socioeconomic status is inversely correlated to fertility. Using crude average fertility rates, sole-ethnicity Pasifika and Māori ethnic groups still have substantially higher fertility than sole-ethnicity Europeans and Asians ethnic groups, even when simultaneously accounting for age, socioeconomic status, education, and religious affiliation. Christians have more children than individuals reportedly without any religion, and fertility rates drop on average for mothers who have higher formal qualifications. Our findings suggest that cultural, or other ethnic-specific factors differentially affect fertility for Māori, Pasifika, New Zealand European, and Asians as aggregated ethnic categories, respectively. 相似文献
268.
Shanna L. Burke Tianyan Hu Nicole M. Fava Tan Li Miriam J. Rodriguez Katie L. Schuldiner 《Journal of women & aging》2019,31(2):140-164
This study examined biological sex differences in the development of mild cognitive impairment (MCI) and probable Alzheimer’s disease (AD) development as predicted by changes in the hippocampus or white matter hyperintensities. A secondary data analysis of the National Alzheimer’s Coordinating Center Uniform Data Set was conducted. We selected samples of participants with normal cognition at baseline who progressed to MCI (n = 483) and those who progressed to probable AD (n = 211) to determine if hippocampal volume or white matter hyperintensities (WMH) at baseline predicted progression to probable AD or MCI and whether the rate of progression differed between men and women. The survival analyses indicated that changes in hippocampal volumes affected the progression to probable AD (HR = 0.535, 95% CI [0.300–0.953]) only among women. White men had an increased rate of progression to AD (HR = 4.396, CI [1.012–19.08]; HR = 4.665, 95% CI [1.072–20.29]) compared to men in other race and ethnic groups. Among women, increases in hippocampal volume ratio led to decreased rates of progressing to MCI (HR = 0.386, 95% CI [0.166–0.901]). Increased WMH among men led to faster progression to MCI (HR = 1.048. 95% CI [1.011–1.086]). Women and men who were older at baseline were more likely to progress to MCI. In addition, results from longitudinal analyses showed that women with a higher CDR global score, older age at baseline, or more disinhibition symptoms experienced higher odds of MCI development. Changes in hippocampal volumes affect the progression to or odds of probable AD (and MCI) more so among women than men, while changes in WMH affected the progression to MCI only among men. 相似文献
269.
One of the core goals of intercultural education is to develop critical and empathic reflection on social justice, particularly as related to humanistic choices and how individuals can counteract exclusion. The present article analyses the Values and Knowledge Education (VaKE) approach, which is aimed at raising awareness about implicit value-oriented priorities in decision-making. Through the Human Development and Capability Approach, the applicability of VaKE’s didactic principles is analysed in relation to young people’s perspectives on resettlement in Europe. The VaKE method was used at a 2013 summer camp in Austria with a culturally diverse group of young Europeans who were presented with a dilemma story that highlighted the complex issue of providing assistance to asylum seekers. The participants engaged in various knowledge and moral viability checks that enabled them to engage with opposing arguments. The participants evidenced critical reflection and self-scrutiny, as well as affiliation and empathic imagination, regarding problems that are encountered by asylum seekers. 相似文献
270.
Dieter Bögenhold Matthias Fink Sascha Kraus 《?sterreichische Zeitschrift für Soziologie》2009,34(3):22-42
In this paper three prominent discourses of Entrepreneurship Research — 1) the Entrepreneur as an actor in society, 2) the embeddedness of the research object of Entrepreneurship Research and 3) the determinants of entrepreneurship processes — are analyzed for possible interfaces between a sociological and economical perspective. This analyses results in a systemized portfolio of research topics, which seem to be especially attractive for such an integrative research approach. The results of a survey of 105 entrepreneurship researchers in the German speaking world underpin the relevance of the identified interfaces and allow for their priorization. That way we contribute to an integration of this field as the presented set of identified interfaces, in a first step, provides a feasible agenda for interdisciplinary (empirical) follow-up research whose results — in a second step — can build elements of an integrative concept of Entrepreneurship Research. 相似文献