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301.
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   
302.
Bitcoin and its peculiar, decentralized transaction system, have already ignited interest by professional and retail traders in search for profits and by economists and legal experts, looking for possible regulation to contain illegal uses. We instead examine the unexpected and ongoing success of Bitcoin from a sociological perspective, first questioning its unusual legitimation system, backed by the so called ‘blockchain technology’, instead of by governmental authorities. Then we collect data and elements to reconstruct Bitcoin’s history as a cryptocurrency, starting from the mysterious story surrounding its birth. We then follow its spread and development through social networks and words of mouth, together with its sudden booms and bursts, finally to suggest that both users and institutional regulators should be aware of the risks of Bitcoin and of its alleged power to challenge our very notion of money.  相似文献   
303.
International coopetition has rarely been studied in relation to innovation. Further exploration of effects of international coopetition, i.e. the pursuit of simultaneous cooperation and competition, on a firm’s innovation performance is especially important as such a relationship is challenging with a high propensity to fail. This observation formed the point of departure for this study, which aims to increase the understanding of the effects of international coopetition on firm innovativeness and how these effects are conditioned on the magnitude of the organizational adjustments a firm introduces. We use an unbalanced panel of 9839 firms that participated in four waves of the Swedish Community Innovation Survey between 2008 and 2014 as our empirical base. We illustrate that firms that cooperate with competitors internationally are more likely to exhibit higher propensity to introduce radical innovations, yet this effect is conditioned upon the magnitude of organizational adjustments. Overall, our study contributes to the understanding of the implications of international coopetition and what a firm needs to benefit from it.  相似文献   
304.
We examined consistency in self-reports of age at first vaginal sex among 9,399 male and female respondents who participated in Waves III and IV (separated by approximately seven years) of the National Longitudinal Study of Adolescent Health (Add Health). Respondents were coded as consistent if they reported an age at first vaginal intercourse at Wave IV that was within one year of the age they reported at Wave III. Sociodemographic, behavioral, and cognitive predictors of consistency were examined using bivariate and multivariate logistic regression. Overall, 85.43% of respondents were able to provide consistent reports. Among both males and females, consistency was associated with age, years since first vaginal intercourse, race/ethnicity, and lifetime number of other-sex partners in final multivariate models. Respondents who were older and had more recently had their first sexual experience were more likely to be consistent. For females only, those who reported a history of nonparental, physically forced sex were less likely to be consistent. Most young adults consistently report age at first vaginal intercourse, supporting the credibility of retrospective self-reports about salient sexual events such as timing of first vaginal intercourse.  相似文献   
305.
Prior to the Taxpayer Relief Act of 1997 (TRA97), the capital gain from the sale of a home was taxed differently for those over and under the age of 55. TRA97 eliminated this differential treatment. Using a difference‐in‐difference approach, we find that home sellers slightly under the age of 55 were 6.2% more likely to move for a less expensive house to maintain, 6.6% less likely to move for a larger place, and 5.2% more likely to reside in a condominium after TRA97's enactment, relative to those slightly over 55. (JEL H24, R21)  相似文献   
306.
Public participation in the planning and design of major public infrastructure and construction (PIC) projects is crucial to their success, as the interests of different stakeholders can be systematically captured and built into the finalised scheme. However, public participation may not always yield a mutually acceptable solution, especially when the interests of stakeholders are diverse and conflicting. Confrontations and disputes can arise unless the concerns or needs of the community are carefully analysed and addressed. The aim of the paper is to propose a systematic method of analysing stakeholder concerns relating to PIC projects by examining the degree of consensus and/or conflict involved. The results of a questionnaire survey and a series of interviews with different entities are provided, which indicate the existence of a significant divergence of views among stakeholder groups and that conflicts arise when there is a mismatch between peoples’ perception concerning money and happiness on the one hand and development and damages on the other. Policy and decision-makers should strive to resolve at least the majority of conflicts that arise throughout the lifecycle of major PIC projects so as to maximise their chance of success.  相似文献   
307.
Research suggests that age and organizational factors are consistently linked with job stress, burnout, and intent to leave among child protection workers. However, no study has contextualized how age matters with regards to these adverse employee outcomes. We conducted a theory driven path analysis that identifies sources of employment-based social capital, job stress, burnout, and intent to leave among two age groups. We used a statewide purposive sample of 209 respondents from a public child welfare organization in a New England state in the United States. Results suggest that the paths to job stress, burnout and intent to leave differed by age group. Social capital dimensions were more influential in safeguarding against job stress for older workers compared to younger workers. Our results justify creating workplace interventions for younger workers that target areas of the organization where relational support could enhance the quality of social interactions within the organization. Organizations may need to establish intervention efforts aimed at younger workers by creating different structures of support that can assist them to better deal with the pressures and demands of child protection work.  相似文献   
308.
Prescribing medications for off-label uses is not illegal. Off-label prescribing includes using medications for unapproved indications; using a drug outside of the recommended dosage range or duration of use; using a drug in certain unapproved patient populations, such as those defined by age, sex, or particular clinical parameters; or intentionally using a medication in a patient who has a known contraindication. Medications would be considered appropriate for off-label use based on their known clinical pharmacology, evidence from clinical studies, and sometimes from the personal experience of the prescriber. The decision to use a drug off label should be based on a careful assessment of the patient's treatment history and the drug's potential risks and benefits. Patients should be given adequate informed consent about how the drug is being used off label and why, along with appropriate information about known risks and side effects.  相似文献   
309.
This study investigated socio-economic impacts of land use change, giving explicit attention to the relationships between independently observed land use change and associated socio-economic changes, perceived land use change and socio-economic change, attributed cause of change, and experienced impacts of change. Using a case study region in south-east Australia, we examined the impacts of growth in use of land for dairy farming, cropping, blue gum plantations and rural residential development on (i) rural population trends, and (ii) the amount and nature of employment available in the study region. Perceptions and impacts of change were assessed using multiple qualitative and quantitative methods. Results demonstrate that local residents were not always aware of the extent and nature of land use change, and had difficulty attributing social changes and their impacts to the land use changes that underlie them. Furthermore, the felt impacts of land use change appeared dependent on a person's awareness of that change, and on their beliefs about the causes of social change. These findings highlight avenues for theoretical development to better specify the processes by which social change processes are experienced as human impacts. The findings also have implications for land use policy and social impact assessment, illustrating the importance of understanding both perceived and actual social change.  相似文献   
310.
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