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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   
2.
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   
3.
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   
4.
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   
5.
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   
6.
In pest risk assessment it is frequently necessary to make management decisions regarding emerging threats under severe uncertainty. Although risk maps provide useful decision support for invasive alien species, they rarely address knowledge gaps associated with the underlying risk model or how they may change the risk estimates. Failure to recognize uncertainty leads to risk‐ignorant decisions and miscalculation of expected impacts as well as the costs required to minimize these impacts. Here we use the information gap concept to evaluate the robustness of risk maps to uncertainties in key assumptions about an invading organism. We generate risk maps with a spatial model of invasion that simulates potential entries of an invasive pest via international marine shipments, their spread through a landscape, and establishment on a susceptible host. In particular, we focus on the question of how much uncertainty in risk model assumptions can be tolerated before the risk map loses its value. We outline this approach with an example of a forest pest recently detected in North America, Sirex noctilio Fabricius. The results provide a spatial representation of the robustness of predictions of S. noctilio invasion risk to uncertainty and show major geographic hotspots where the consideration of uncertainty in model parameters may change management decisions about a new invasive pest. We then illustrate how the dependency between the extent of uncertainties and the degree of robustness of a risk map can be used to select a surveillance network design that is most robust to knowledge gaps about the pest.  相似文献   
7.
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   
8.
The article describes the technology transfer concerns reported by a small sample (N=14) of recent college graduates with disabilities. In structured, in-depth interviews, researchers asked respondents to reflect on the extent to which they had utilized technology resources during their college years in preparation for the world of work. Results suggest that colleges and universities need to play a more active role in introducing students with disabilities to both generalized and assistive technology services.  相似文献   
9.
Quality Management: History, problems and an integrative modelStarting with a critical examination of the history and the commonly known concepts and systems of Quality Management, the paper discusses a broader understanding of quality in a genuinely managerial perspective. This is shown by generating and applying five basic dimensions of the quality concept. An integrative concept of Quality Management is presented.  相似文献   
10.
When candidates assume issue positions opposite those of their sponsoring political party do citizens recognize these positions? Relatedly, what role do candidates' actual issue positions play in citizens' perceptions of their issue positions? Examining citizens' perceptions of 1996 and 1998 House candidates' position on abortion, this research finds that citizens' perceptions are shaped largely by partisan and, to a lesser extent, gender stereotypes. However, candidates' individuating positions on abortion influence perceptions of the candidates' position, but the effects are considerably stronger for perceptions of Republican candidates. Democratic candidates are likely to adopt anti-abortion positions in districts characterized by lower than average levels of political awareness and education, reducing the likelihood their party-contradicting position is accurately perceived. In contrast, Republican candidates adopt a pro-choice position in districts characterized by high education and political awareness, increasing the likelihood their position is accurately perceived.  相似文献   
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