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371.
Cameron C. Brown Zenova Williams Jared A. Durtschi 《Journal of marital and family therapy》2019,45(4):650-667
Minimal research has examined interracial couples’ relationship satisfaction and dissolution patterns over time. Using dyadic data across 8 years, we examined potential differences in relationship quality trajectories through latent growth curve modeling with 1,336 couples as well as differential risks for relationship dissolution through logistic regression between same‐race and interracial relationships using a different subset of 2,370 couples. Results indicated that women in interracial relationships were significantly lower in initial relationship quality than women in same‐race relationships. Further, interracial couples of Black‐Hispanic partnerings were twice as likely to separate across 8 years than same‐race couples. These results suggest that despite interracial relationships not substantively differing from same‐race couples in trajectories of relationship quality, specific Black‐Hispanic interracial couples are at a higher risk of eventual separation. 相似文献
372.
We analyse 4300 advertisements of children featured in the Today's Child column, a daily written by Helen Allen in The Toronto Telegram and The Toronto Star from 1964 to 1982, to understand how the Canadian public became accepting of the adoption of Indigenous children. While children of all ethnic backgrounds were featured, the Indigenous children who were displayed were part of a larger system of child removal, known as the ‘Sixties Scoop’. We demonstrate the ways Indigenous children are described with a specific form of happiness that is conjoined with colonial conceptions of the family and nation. 相似文献
373.
Anthony Y. C. Kuk 《Journal of Statistical Computation and Simulation》2019,89(11):2138-2150
In survival analysis, one way to deal with non-proportional hazards is to model short-term and long-term hazard ratios. The existing model of this nature has no control over how fast the hazard ratio is changing over time. We add a parameter to the existing model to allow the hazard ratio to change over time at different speed. A nonparametric maximum likelihood approach is used to estimate the model parameters. The existing model is a special case of the extended model when the speed parameter is 0, which leads naturally to a way of testing the adequacy of the existing model. Simulation results show that there can be substantial bias in the estimation of the short-term and long-term hazard ratio if the speed parameter is fixed incorrectly at 0 rather than estimated. The extended model is fitted to three real data sets to shed new insights, including the observation that converging hazards does not necessarily imply the odds are proportional. 相似文献
374.
In recent decades, quantile regression has received much more attention from academics and practitioners. However, most of existing computational algorithms are only effective for small or moderate size problems. They cannot solve quantile regression with large-scale data reliably and efficiently. To this end, we propose a new algorithm to implement quantile regression on large-scale data using the sparse exponential transform (SET) method. This algorithm mainly constructs a well-conditioned basis and a sampling matrix to reduce the number of observations. It then solves a quantile regression problem on this reduced matrix and obtains an approximate solution. Through simulation studies and empirical analysis of a 5% sample of the US 2000 Census data, we demonstrate efficiency of the SET-based algorithm. Numerical results indicate that our new algorithm is effective in terms of computation time and performs well for large-scale quantile regression. 相似文献
375.
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
376.
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
377.
Philippe-Benoit Côté 《Journal of social service research》2019,45(3):429-443
The sexual health problems experienced by homeless youth bring into question their use of available sexual health services. Using a qualitative typological analysis, this study aims to identify sexual health services utilization profiles for homeless youth, and to understand the role of the homeless experience on the utilization of sexual health services. Individual interviews were conducted with 33 homeless youth (17 men, 16 women) between 18 and 25?years of age. Typological analysis identified four profiles: (1) a targeted use of sexual health services to determine one’s serological status following a relational change during the homeless experience; (2) a limited use of sexual health services to manage sexual emergencies that arise during the homeless experience; (3) a regular use of sexual health services to avoid the risks associated with the homeless experience; (4) a frequent use of sexual health services to obtain support when engaging in prostitution during the homeless experience. This study shows that the precarious and unstable conditions within the homeless experience incite youth to utilize sexual health services in different ways. These findings point to the importance of rethinking sexual health services to better adapt them to the different utilization profiles of homeless youth. 相似文献
378.
Charlotta Sirén Pankaj C. Patel Daniel Örtqvist Joakim Wincent 《Long Range Planning》2018,51(6):953-971
Despite the possibility of burnout resulting from dynamics in firms' upper echelons, little if any work has focused on chief executive officer's (CEO's) burnout and firm performance. Drawing on managerial discretion theory, this article analyzes the influence of CEO burnout on firm performance and the moderating roles of the individual (CEO locus of control), structural power (CEO duality and CEO tenure), and organizational characteristics (size, age, and resource availability) related to managerial discretion. Using a sample of 156 CEOs in Swedish firms, we find a negative association between CEOs who report higher burnout and firm performance. Our results confirm that CEO duality and resource availability ameliorate and firm size exacerbates the negative association between CEO burnout and firm performance. Contrary to our expectations, CEO locus of control, CEO tenure, and firm age do not influence this relationship. We discuss the implications of our research for upper echelons theory and strategic leadership theory. 相似文献
379.
This study investigates the impact of service diversification on the rate and mode of firm growth in professional service firms (PSFs). Drawing on the extant PSF literature, we identify differing views regarding the growth impact of service diversification. Specifically, some scholars suggest that the external client benefits associated with service diversification should allow PSFs to expand revenues at a rapid pace and pursue less merger and acquisition activity, whereas others imply that increased diversification can cause internal challenges with respect to learning costs, coordination and innovation that can limit the rate of revenue growth and encourage more mergers and acquisitions. We test these competing views using longitudinal data on 137 accounting firms and cross-sectional data on 125 law firms and find that service diversification is negatively associated with the rate of firm revenue growth and positively associated with the use of mergers and acquisitions. 相似文献
380.
Vladyslav Kushnir Alexandra Godinho David C. Hodgins Christian S. Hendershot John A. Cunningham 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2018,34(4):1407-1421
Most problem gamblers do not seek formal treatment, recovering on their own through cognitive re-appraisal or self-help strategies. Although barriers to treatment have been extensively studied, there is a paucity of research on self-directed changes in problem gambling and very few studies have examined these changes prospectively. The aim of this study was to examine the trajectory of gambling severity and behavior change over an 18-month period, among a sample of non-treatment seeking/attending problem gamblers recruited from the community (N?=?204) interested in quitting or reducing gambling. Separate mixed effects models revealed that in absence of formal treatment, significant reductions in gambling severity, frequency, and amount gambled could be observed over the course of a 6 to 9-month period and that changes experienced within the first 12 months were maintained for an extended 6 months. Problem gambling severity at baseline was significantly associated with changes in severity over time, such that participants with more severe gambling problems demonstrated greater reductions in their gambling severity over time. A total of 11.1% of participants gambled within a low-risk threshold at 18 months, although 28.7% of the sample reported consecutive gambling severity scores below problem levels for the duration of 1 year or longer. The findings suggest that among problem gamblers motivated to quit or reduce their gambling, significant self-directed changes in gambling severity can occur over a relatively short time. Additional prospective studies are needed to document the role of specific self-help tools or thought processes in exacting gambling changes. 相似文献