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1.
A number of researchers have recently challenged the long-held notion among criminologists that rape, along with most other violent crimes, is an intraracial crime. Based on analysis of survey data they concluded that black rapists “prefer” or “seek out” white victims and that the likelihood of a black offender selecting a white victim has been increasing during recent years. Data presented here (1977–88 National Crime Surveys) refute the notion that black rapists “prefer” white victims. Moreover these same data fail to support the contention that rapes involving black offenders and white victims have been increasing. According to National Crime Survey estimates, the proportion of black offenders that victimize whites has been declining. An earlier version of this paper was presented at the annual meetings of the American Society of Criminology, November 1991.  相似文献   
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In confirmatory clinical trials, the prespecification of the primary analysis model is a universally accepted scientific principle to allow strict control of the type I error. Consequently, both the ICH E9 guideline and the European Medicines Agency (EMA) guideline on missing data in confirmatory clinical trials require that the primary analysis model is defined unambiguously. This requirement applies to mixed models for longitudinal data handling missing data implicitly. To evaluate the compliance with the EMA guideline, we evaluated the model specifications in those clinical study protocols from development phases II and III submitted between 2015 and 2018 to the Ethics Committee at Hannover Medical School under the German Medicinal Products Act, which planned to use a mixed model for longitudinal data in the confirmatory testing strategy. Overall, 39 trials from different types of sponsors and a wide range of therapeutic areas were evaluated. While nearly all protocols specify the fixed and random effects of the analysis model (95%), only 77% give the structure of the covariance matrix used for modeling the repeated measurements. Moreover, the testing method (36%), the estimation method (28%), the computation method (3%), and the fallback strategy (18%) are given by less than half the study protocols. Subgroup analyses indicate that these findings are universal and not specific to clinical trial phases or size of company. Altogether, our results show that guideline compliance is to various degrees poor and consequently, strict type I error rate control at the intended level is not guaranteed.  相似文献   
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Since decades, the financial industry has experienced a continuous evolution in service delivery due to digitalization. This evolution is characterized by expanded connectivity and enhanced speed of information processing both at the customer interface and in back-office processes. Recently, there has been a shift in the focus of digitalization from improving the delivery of traditional tasks to introducing fundamentally new business opportunities and models for financial service companies. Digital Finance encompasses a magnitude of new financial products, financial businesses, finance-related software, and novel forms of customer communication and interaction—delivered by FinTech companies and innovative financial service providers. Against this backdrop, the research on finance and information systems has started to analyze these changes and the impact of digital progress on the financial sector. Therefore, this article reviews the current state of research in Digital Finance that deals with these novel and innovative business functions. Moreover, it gives an outlook on potential future research directions. As a conceptual basis for reviewing this field, the Digital Finance Cube, which embraces three key dimensions of Digital Finance and FinTech, i.e., the respective business functions, the technologies and technological concepts applied as well as the institutions concerned, is introduced. This conceptualization supports researchers and practitioners when orientating in the field of Digital Finance, allows for the arrangement of academic research relatively to each other, and enables for the revelation of the gaps in research.  相似文献   
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This article proposes that there is added value in moving beyond isolated studies of return-related migration policies in order to consider both deportations and so-called assisted voluntary returns under the common heading of ‘state-induced returns’. Based on official documents and interviews with staff members of the United Nations High Commissioner for Refugees and the International Organisation for Migration, it argues that international actors working in the field of migrant return engage in a type of task-sharing that goes beyond functional complementariness. With regard to the return of rejected asylum seekers, for instance, they legitimise each other's engagement as well as the overarching return objectives of governments, and are, therefore, involved in norm-building regarding the acceptability of state-induced returns. In addition to setting certain minimum standards regarding states' treatment of their immigrant population, international actors assist states in upholding control over them. Rather than merely replacing state-led regulation, international actors thus support domestic governments in reaching their migration control objectives, and thereby contribute to a stabilisation of state sovereignty in the governance of migration.  相似文献   
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Employer-provided insurance is the leading source of medical insurance for non-elderly Americans. However, it leaves many without coverage. Evidence suggests that the non-group insurance market does a poor job of filling in these gaps, for those with both short- and long-term uninsurance. It does so for all income and age groups, as well as for both genders. It does fill some of the gaps in employer-provided coverage for those with middle and high incomes, though very incompletely.  相似文献   
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Photo‐elicited interviews indicate that children hardly ever mention educators when asked about elements in preschool that make them feel happy. Happiness is found to occur in activities in the ‘underlife’ of the ECEC institution. Children challenge adult rules and norms in order to create status in the peer‐group, while at the same time, they seek to construct social identity and maintain a positive relationship with their educators. A child that manages to balance both adult expectations and what is needed to participate in the underlife among peers, experiences happiness and thus, is in a good state of well‐being.  相似文献   
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Reference groups and significant others are vitally important in both the formation and the persistence or change of normative as well as deviant behavior patterns. Thus one's initial religious beliefs and behavior (or lack thereof) reflect the socializing influence of the family. However, the situation may change when young people leave home for education or work, as demonstrated by research that shows decreases in religious beliefs or church attendance when young people leave home to attend college. In contrast to the pattern whereby religiosity declines in a college or university environment, we maintain that students who develop close ties with others who are religious, especially in a highly religious community, will maintain the same patterns of high commitment developed in their families. Specifically, we hypothesize that religious beliefs and participation will be positively related to (1) parents' religious beliefs and practices and (2) current friends' religious beliefs and participation. These hypotheses were tested with a sample of college students living on campus (n = 339). The data support the argument that students' current religious beliefs and behavior are related to both their parents' religiosity and the reinforcing effects of the religiosity of their current friends.  相似文献   
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Nonindigenous species have caused significant impacts to North American forests despite past and present international phytosanitary efforts. Though broadly acknowledged, the risks of pest invasions are difficult to quantify as they involve interactions between many factors that operate across a range of spatial and temporal scales: the transmission of invading organisms via various pathways, their spread and establishment in new environments. Our study presents a stochastic simulation approach to quantify these risks and associated uncertainties through time in a unified fashion. We outline this approach with an example of a forest pest recently detected in North America, Sirex noctilio Fabricius. We simulate new potential entries of S. noctilio as a stochastic process, based on recent volumes of marine shipments of commodities from countries where S. noctilio is established, as well as the broad dynamics of foreign marine imports. The results are then linked with a spatial model that simulates the spread of S. noctilio within the geographical distribution of its hosts (pines) while incorporating existing knowledge about its behavior in North American landscapes. Through replications, this approach yields a spatial representation of S. noctilio risks and uncertainties in a single integrated product. The approach should also be appealing to decisionmakers, since it accounts for projected flows of commodities that may serve as conduits for pest entry. Our 30-year forecasts indicate high establishment probability in Ontario, Quebec, and the northeastern United States, but further southward expansion of S. noctilio is uncertain, ultimately depending on the impact of recent international treatment standards for wood packing materials.  相似文献   
10.
In this paper we compare expectations derived from 10 different human physiologically based pharmacokinetic models for perchloroethylene with data on absorption via inhalation, and concentrations in alveolar air and venous blood. Our most interesting finding is that essentially all of the models show a time pattern of departures of predictions of air and blood levels relative to experimental data that might be corrected by more sophisticated model structures incorporating either (a) heterogeneity of the fat compartment (with respect to either perfusion or partition coefficients or both) or (b) intertissue diffusion of perchloroethylene between the fat and muscle/VRG groups. Similar types of corrections have recently been proposed to reduce analogous anomalies in the fits of pharmacokinetic models to the data for several volatile anesthetics.(17-20) A second finding is that models incorporating resting values for alveolar ventilation in the region of 5.4 L/min seemed to be most compatible with the most reliable set of perchloroethylene uptake data.  相似文献   
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