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781.
To perform variable selection in expectile regression, we introduce the elastic-net penalty into expectile regression and propose an elastic-net penalized expectile regression (ER-EN) model. We then adopt the semismooth Newton coordinate descent (SNCD) algorithm to solve the proposed ER-EN model in high-dimensional settings. The advantages of ER-EN model are illustrated via extensive Monte Carlo simulations. The numerical results show that the ER-EN model outperforms the elastic-net penalized least squares regression (LSR-EN), the elastic-net penalized Huber regression (HR-EN), the elastic-net penalized quantile regression (QR-EN) and conventional expectile regression (ER) in terms of variable selection and predictive ability, especially for asymmetric distributions. We also apply the ER-EN model to two real-world applications: relative location of CT slices on the axial axis and metabolism of tacrolimus (Tac) drug. Empirical results also demonstrate the superiority of the ER-EN model. 相似文献
782.
zlem Kaymaz Khaled Alqahtani Henry M. Wood Arief Gusnanto 《Journal of applied statistics》2021,48(4):605
The purpose of this study is to highlight the application of sparse logistic regression models in dealing with prediction of tumour pathological subtypes based on lung cancer patients'' genomic information. We consider sparse logistic regression models to deal with the high dimensionality and correlation between genomic regions. In a hierarchical likelihood (HL) method, it is assumed that the random effects follow a normal distribution and its variance is assumed to follow a gamma distribution. This formulation considers ridge and lasso penalties as special cases. We extend the HL penalty to include a ridge penalty (called ‘HLnet’) in a similar principle of the elastic net penalty, which is constructed from lasso penalty. The results indicate that the HL penalty creates more sparse estimates than lasso penalty with comparable prediction performance, while HLnet and elastic net penalties have the best prediction performance in real data. We illustrate the methods in a lung cancer study. 相似文献
783.
Richard M. Auty 《Development policy review : the journal of the Overseas Development Institute》1995,13(3):195-218
Whatever the theoretical merits of an industrial policy, in practice state incentives in support of infant industry are difficult to withdraw once they have been granted. Infant maturation is thereby delayed, resulting in ‘policy capture’ which confers rents on the assisted firms at the expense of consumers and/or taxpayers. The process is well-documented in poorly managed economies pursuing autarkic industrial policies (Auty, 1994a). This article examines evidence of policy capture in well-managed economies pursuing competitive industrial policies. Examples are drawn from the heavy (and chemical) industry drives of South Korea (hereafter Korea) and Taiwan, but the research is first set in the context of the industrial policy debate. 相似文献
784.
Over the twentieth and twenty-first centuries, veterans have been more likely to enter into race/ethnic intermarriages than non-veterans. Theories of race/ethnic intermarriage variously point to how minority race/ethnicity, race/ethnically diverse social settings, progressive racial attitudes, and high socioeconomic status increase individuals’ likelihood of intermarrying. Veterans’ unique racial and socioeconomic characteristics may contribute to their greater likelihood of intermarrying relative to non-veterans: larger percentages of veterans than non-veterans are members of racial and ethnic minority groups, while military service increases individual service members’ long-term economic and educational prospects. At the same time, veterans share in common their exposure to the unique military environment, which may increase their likelihood of intermarriage by diversifying their social circles, and subjecting their attitudes and behavior to group norms that are more explicitly egalitarian than those of society at large. The present study considers these two possible explanations for veterans’ greater likelihood of intermarriage. We use data on seven cohorts of men over six decades in the Current Population Survey, representing a total of 1,456,742 observations, to decompose the difference in likelihood of racial intermarriage between veterans and non-veterans among married men aged 18–65. We find that across cohorts and decades, veterans’ greater likelihood of intermarrying is not fully explained by their race/ethnic and socioeconomic composition. We argue that veterans’ greater likelihood of intermarrying may therefore be driven by their exposure to the military environment. 相似文献
785.
786.
Although subprime mortgage lending and unemployment were largely responsible for the wave of foreclosures during the Great Recession, additional sources of financial risk may have exacerbated the crisis. We hypothesize that many parents sending children to college were financially overextended and vulnerable to foreclosure as the economy contracted. With commuting zone panel data from 2006 to 2011, we show that increasing rates of college attendance across the income distribution in one year predict a foreclosure rate increase in subsequent years, net of fixed characteristics and changes in employment, refinance debt, house prices, and 19-year-old population size. We find similar evidence of college-related foreclosure risk using longitudinal household data from the Panel Study of Income Dynamics. Our findings uncover a previously overlooked dimension of the foreclosure crisis, and highlight mortgage insecurity as an inadvertent consequence of parental investment in higher education. 相似文献
787.
We study prevalence of son preference in families of East and South Asian origin living in the USA by investigating parental time investments in children using American Time Use Surveys. Estimates show that East and South Asian mothers spend an additional hour of quality time per day with their young (aged 0–2 years) sons than with young daughters; son preference in mothers’ time allocation declines as children get older. East and South Asian fathers’ time with young children is gender neutral. We find gender specialization in time with children aged 6–17 with fathers spending more time with sons and mothers spending more time with daughters. 相似文献
788.
Gemma M. Carney 《Journal of women & aging》2018,30(3):242-258
The article proposes a Gender Politics of Aging approach to the study of aging societies. The approach recognizes the feminization of old age, ageism’s roots in sexist discourse, and the need to recognize the role of politics in driving demographic debates. Drawing together arguments from feminist gerontology and political demography, the article argues that the intersection of politics and gender must be considered if appropriate responses to an older, feminized demography are to be produced. I conclude that the work of aging feminists provides a rich vein of research and praxis from which a gender politics of aging approach can draw. 相似文献
789.
Kathleen M. Baird Amornrat S. Saito Jennifer Eustace Debra K. Creedy 《Women and birth : journal of the Australian College of Midwives》2018,31(4):285-291
Background
Asking women about experiences of domestic violence in the perinatal period is accepted best practice. However, midwives and nurses may be reluctant to engage with, or effectively respond to disclosures of domestic violence due a lack of knowledge and skills.Aim
To evaluate the impact of training on knowledge and preparedness of midwives and nurses to conduct routine enquiry about domestic violence with women during the perinatal period.Method
A pre-post intervention design was used. Midwives and nurses (n = 154) attended a full day workshop. Of these, 149 completed pre-post workshop measures of knowledge and preparedness. Additional questions at post-training explored participants’ perceptions of organisational barriers to routine enquiry, as well as anticipated impact of training on their practice. Training occurred between July 2015 and October 2016.Findings
Using the Wilcoxon signed-rank test, all post intervention scores were significantly higher than pre intervention scores. Knowledge scores increased from a pre-training mean of 21.5–25.6 (Z = ?9.56, p < 0.001) and level of preparedness increased from 40.8 to 53.2 (Z = ?10.12, p < 0.001). Most participants (93%) reported improved preparedness to undertake routine enquiry after training. Only a quarter (24.9%) felt their workplace allowed adequate time to respond to disclosures of DV.Conclusions
Brief training can improve knowledge, preparedness, and confidence of midwives and nurses to conduct routine enquiry and support women during the perinatal period. Training can assist midwives and nurses to recognise signs of DV, ask women about what would be helpful to them, and address perceived organisational barriers to routine enquiry. Practice guidelines and clear referral pathways following DV disclosure need to be implemented to support gains made through training. 相似文献790.
Rebecca A. Chedid Rowan M. Terrell Karen P. Phillips 《Women and birth : journal of the Australian College of Midwives》2018,31(4):e223-e231