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51.
Response‐adaptive randomisation (RAR) can considerably improve the chances of a successful treatment outcome for patients in a clinical trial by skewing the allocation probability towards better performing treatments as data accumulates. There is considerable interest in using RAR designs in drug development for rare diseases, where traditional designs are not either feasible or ethically questionable. In this paper, we discuss and address a major criticism levelled at RAR: namely, type I error inflation due to an unknown time trend over the course of the trial. The most common cause of this phenomenon is changes in the characteristics of recruited patients—referred to as patient drift. This is a realistic concern for clinical trials in rare diseases due to their lengthly accrual rate. We compute the type I error inflation as a function of the time trend magnitude to determine in which contexts the problem is most exacerbated. We then assess the ability of different correction methods to preserve type I error in these contexts and their performance in terms of other operating characteristics, including patient benefit and power. We make recommendations as to which correction methods are most suitable in the rare disease context for several RAR rules, differentiating between the 2‐armed and the multi‐armed case. We further propose a RAR design for multi‐armed clinical trials, which is computationally efficient and robust to several time trends considered.  相似文献   
52.
Urban Ecosystems - Free-ranging domestic dogs are the world most common exotic carnivore species that could negatively interact with the native wildlife as predators, competitors, and disease...  相似文献   
53.
The uneven development of minimum incomes in Spain is one of the factors that explain the significant differences in the poverty indicators that characterize the Spanish regions, generally in favour of the territories most committed to these policies (Basque Country, Navarra and Asturias). However, there are other aspects that deserve some consideration when interpreting the specific method of developing minimum incomes in southern Europe. One aspect has to do with the differing dynamics of countries, such as Spain and Italy, which have opted for a decentralized regional model. In this regard, the regional autonomous initiative of the Basque Country played a decisive role in promoting minimum income programs in the late 1980s. Without its leadership in the launch of the regional minimum income policy, Spanish trade unions would probably not have opted for this method as a mechanism for combating poverty in the 1990s. No Italian region went on to play this driving role at that time. This article analyses the ideological foundations of the Basque minimum income policy introduced in the late 1980s and which grew significantly before and during the crisis that started in 2007-2008. It examines the dominant political narrative on this issue by analysing the discourse of some of the key nationalist leaders involved in the birth and development of the minimum income scheme. The approach shows that the experience of social decline linked to industrial restructuring processes was instrumental in the construction of the nationalist narrative.  相似文献   
54.
Research on the determinants of foreign aid tends to focus on the relationship between donor country priorities and recipient state characteristics, but donors also make decisions about which organizations and programs within countries will receive assistance. Although NGOs increasingly have been recipients of foreign aid, few data are available to investigate which organizations within a given country receive that funding. Donors may prioritize structural characteristics of NGOs or their local ties—or they may seek a combination that blends concern about efficiency and accountability with an interest in developing national civil society. We use original data from Cambodia to explore whether aid is likely to go to managerial organizations (professionalized NGOs and NGOs that utilize modern management tools) or to organizations that are embedded in the domestic context. We argue that managerialism provides legitimacy for NGOs by signaling capacity and accountability to donors, increasing the likelihood of government funding. We argue that local embeddedness also confers legitimacy by aligning community ties and networks to rights-based development, increasing the likelihood of government funding. We find general support for the managerialism argument, but donor agencies do not prioritize direct funding for “indigenous” NGOs—not even among those with high levels of managerialism.  相似文献   
55.
Spain is suffering an important economic slowdown which affects significantly to unemployment rises. For this reason, many individuals are considering to increase their educational level. However, this decision can lead to get worse labor market indicators. In this paper, we analyze the problem of over-education in Spain and its effect on earnings. Using the last four waves (2009–2012) of the European Union Statistics on Income and Living Conditions (EU-SILC, 2009–2012) this study analyses over-education situation of employed people and compares over-education rates and earnings of these individuals. Cross-sectional analysis (focused on a recent period of time) is performed. We apply different matching techniques based on propensity score methods to evaluate the impact of over-education on personal earnings. The results obtained in this paper add more empirical evidence supporting the effect of education on earnings together with occupational placement because over-education could be a great problem for many countries. In Spain, there exists a problem of over-education which varies among occupations. Overeducated workers are most likely to be found among “Service workers and shop and market sales workers” and “Elementary occupations”. Also, the majority of individuals working as “Professionals” are adequately educated. Besides, over-education has a significant negative impact on earnings. Although the results depend on the way we define over-education (interval or modal method), those individuals over-educated receive less earnings than they correspond to. In fact, the decrease can reach about 5000 euro per year.  相似文献   
56.
57.
Dysfunctional sexual beliefs are vulnerability factors for sexual dysfunction. This cross-sectional study aimed to test the mediating role of cognitive distraction on the relationship between dysfunctional sexual beliefs about sexual functioning shared by men and women and sexual function. The authors used a sample of 421 cisgender heterosexual participants involved in a monogamous relationship. The hypothesized mediation model was tested using a bootstrapped cross product of coefficients approach. Results showed a significant negative, indirect effect between dysfunctional sexual beliefs and women's sexual function through cognitive distraction. The discussion of this study highlights the importance of cognitive factors in sexual functioning.  相似文献   
58.
Word clouds constitute one of the most popular statistical tools for the visual analysis of text documents because they provide users with a quick and intuitive understanding of the content. Despite their popularity for visualizing single documents, word clouds are not appropriate to compare different text documents. Independently generating word clouds for each document leads to configurations where the same word is typically located in widely different positions. This makes it very difficult to compare two or more word clouds. This paper introduces COWORDS, a new stochastic algorithm to create multiple word clouds, including one for each document. The shared words in multiple documents are placed in the same position in all clouds. Similar documents produce similar and compact clouds, making it easier to simultaneously compare and interpret several word clouds. The algorithm is based on a probability distribution in which the most probable configurations are those with a desirable visual aspect, such as a low value for the total distance between the words in all clouds. The algorithm output is a set of word clouds that are randomly selected from this probability distribution. The selection procedure uses a Markov chain Monte Carlo simulation method. We present several examples that illustrate the performance and visual results that can be obtained by our algorithm.  相似文献   
59.
The pathways between differentiation of self and health remain only partly elucidated. This cross‐cultural study sought to test Bowen's hypothesis about the associations between differentiation, stressful life events, and physical and psychological health, in a sample of 466 Spanish adults. Results show that people with higher levels of differentiation were less prone to physical ailments (e.g., heart disease, cancer, or blood disorders) and psychological symptoms (e.g., depression or anxiety). Further, differentiation mediated the association between stress (i.e., perceived negativity of stress in the past year and number of stressful events across the lifetime) and physical and psychological health. The current research provides cross‐cultural empirical evidence for the links between differentiation and mind and body health in a Mediterranean culture.  相似文献   
60.
VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - A social business responds to social problems usually ignored by institutions, mobilizing resources and generating...  相似文献   
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