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971.
We study a principal‐agent relationship between a politician and a researcher that captures stylized facts regarding the involvement of politics into scientific research. The politician has some ideal policy that he would like to implement, but needs to contract with a researcher to choose a policy that is supported by scientific advice. We study the implemented contracts under symmetric and under asymmetric information about the researcher's ability and concern for reputation, and discuss with which types of researchers the politician will contract. We identify several conflicts between the interests of voters and those of the politician. (JEL D72, D82, D83)  相似文献   
972.
Next‐generation sequencing (NGS) data present an untapped potential to improve microbial risk assessment (MRA) through increased specificity and redefinition of the hazard. Most of the MRA models do not account for differences in survivability and virulence among strains. The potential of machine learning algorithms for predicting the risk/health burden at the population level while inputting large and complex NGS data was explored with Listeria monocytogenes as a case study. Listeria data consisted of a percentage similarity matrix from genome assemblies of 38 and 207 strains of clinical and food origin, respectively. Basic Local Alignment (BLAST) was used to align the assemblies against a database of 136 virulence and stress resistance genes. The outcome variable was frequency of illness, which is the percentage of reported cases associated with each strain. These frequency data were discretized into seven ordinal outcome categories and used for supervised machine learning and model selection from five ensemble algorithms. There was no significant difference in accuracy between the models, and support vector machine with linear kernel was chosen for further inference (accuracy of 89% [95% CI: 68%, 97%]). The virulence genes FAM002725, FAM002728, FAM002729, InlF, InlJ, Inlk, IisY, IisD, IisX, IisH, IisB, lmo2026, and FAM003296 were important predictors of higher frequency of illness. InlF was uniquely truncated in the sequence type 121 strains. Most important risk predictor genes occurred at highest prevalence among strains from ready‐to‐eat, dairy, and composite foods. We foresee that the findings and approaches described offer the potential for rethinking the current approaches in MRA.  相似文献   
973.
Despite their fear of repercussions on career advancement and gender identity, Korean fathers taking parental leave have continually increased. Why do Korean fathers take parental leave in spite of the risk of being stigmatized as less masculine and less ideal workers? Are they willing to be ‘ideological renegades' to be new involved fathers? In‐depth interviews with fathers who took parental leave provide interesting answers. Overall, taking parental leave does not make fathers become ideological renegades since it is mainly utilized in a manner that accommodates the work devotion schema, deviating from the formal policy objectives. This deviant utilization is encouraged and even valued by organizations. This may be part of a psychological contract between organizations and employees, ensuring that employees are dedicated to their career even during parental leave. Furthermore, beyond the legal eligibility of uptake, informal but powerful ‘organizational eligibility' such as high performance or their contribution to the organization, makes not only the likelihood but also the aftermath of taking up different across fathers. As a result, a hierarchy among fathers with class connotations emerges. This hierarchy among fathers, combined with the traditional gender hierarchy, may reinforce the masculine fabric of ideal workers as the norm.  相似文献   
974.
High rates of mortality on long term carcinogenicity studies can often result in challenges when it comes to the statistical analysis of tumor incidence. The current regulatory advice often results in treated groups being terminated earlier than the control group. However, this advice rarely considers the impact of this action on the statistical analyses. The nature of these analyses means that groups terminated at different times may not be directly comparable due to age differences of the animals. Here we discuss the issues related to this and investigate several approaches of how to incorporate these groups within the statistical analyses. Although no single method appears to resolve these issues consistently, inclusion of the early terminated group is still informative. Depending on the timing of the early termination, either pooling of the groups into a single terminal kill (TK) interval or reassignment of intervals based purely on time of death (ie, no separate TK interval) appear preferable. However, to draw meaningful conclusions the time of onset of a given tumor must also be considered alongside incident rates and any statistical findings.  相似文献   
975.
Abstract

Objective: To examine the prevalence of various types of tobacco-free policies among a US national sample of postsecondary educational institutions (PEIs). Participants: A national sample of US PEIs (N?=?605) attended by the participants of the NEXT Generation Health Study. Methods: Tobacco policies of these PEIs were reviewed to determine if they were e-cigarette-free (yes/no), hookah-free (yes/no), and ACHA-recommended tobacco-free (yes/no) in June–December 2017. Logistic regression models were used to examine the relationships between institutional characteristics and tobacco policies. Results: Overall, 39.2, 26.0, and 20.0% of the sample adopted e-cigarette-free, hookah-free, and ACHA-recommended tobacco-free policies, respectively. Proprietary PEIs (vs. public) were less likely to have ACHA-recommended tobacco-free policies, while PEIs in the South and Midwest (vs. West) were more likely to have ACHA-recommended tobacco-free policies (p?<?0.05). Conclusions: Most sampled PEIs did not have ACHA-recommended tobacco-free polices. Subsequent research needs to investigate how ACHA-recommended tobacco policies influence tobacco use.  相似文献   
976.
977.
The spread of COVID‐19 acutely challenges and affects not just economic markets, demographic statistics and healthcare systems, but indeed also the politics of organizing and becoming in a new everyday life of academia emerging in our homes. Through a collage of stories, snapshots, vignettes, photos and other reflections of everyday life, this collective contribution is catching a glimpse of corona‐life and its micro‐politics of multiple, often contradicting claims on practices as many of us live, work and care at home. It embodies concerns, dreams, anger, hope, numbness, passion and much more emerging amongst academics from across the world in response to the crisis. As such, this piece manifests a shared need to — together, apart — enact and explore constitutive relations of resistance, care and solidarity in these dis/organizing times of contested spaces, identities and agencies as we are living–working–caring at home during lockdowns.  相似文献   
978.
From a traditional viewpoint, fathers are seen as the main disciplinarian in the family. However, recent studies suggest that these traditional family role patterns may have changed. In this study, we observed discipline strategies of mothers and fathers toward their sons and daughters. Participants included 242 families with two children (1 and 3 years of age). Findings revealed that parental discipline varied by the age of the children, but that mothers disciplined their children more often than fathers. Fathers, conversely, showed more laxness in response to child non‐compliance. Gender of the children was only related to physical interference, with mothers using more physical interference with boys than fathers, irrespective of birth order. Taken together, these findings highlight the importance of parent gender for parent–child interactions in early childhood, but also suggest that child age should be taken into account as important explanatory factors.  相似文献   
979.
While theory suggests that information programs may correct market failures and improve welfare, the empirical impacts of these policies remain undetermined. We show that mandatory disclosure programs in the electricity industry achieve stated policy goals. We find that the proportion of fossil fuels decreases, and the proportion of clean fuels increases in response to disclosure programs. However, the programs may produce unintended consequences. For example, programs may make “clean” firms cleaner, while leaving “dirty” firms relatively unchanged. If the marginal benefits of pollution abatement are larger at dirty firms than at clean firms, disclosure programs may induce inefficient abatement allocations. (JEL D83, Q58, D21)  相似文献   
980.
Abstract

Recent debates about same-sex marriage have raised questions concerning the interchangeability of mothers and fathers. This paper provides three pieces of empirical evidence that highlight the distinct role that fathers and mothers play in the home. First, we use time-use data to show that fathers and mothers provide different amounts of time to their children regardless of who is the breadwinner in the household. Second, we show that men and women choose different occupations, with men more likely to choose occupations that have a protective role and mothers more likely to choose an occupation with a nurturing role. Third, we find that children are much less likely to experience domestic violence and neighborhood violence when there is a father in the home.  相似文献   
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