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131.
Neural networks are a popular machine learning tool, particularly in applications such as protein structure prediction; however, overfitting can pose an obstacle to their effective use. Due to the large number of parameters in a typical neural network, one may obtain a network fit that perfectly predicts the learning data, yet fails to generalize to other data sets. One way of reducing the size of the parmeter space is to alter the network topology so that some edges are removed; however it is often not immediately apparent which edges should be eliminated. We propose a data-adaptive method of selecting an optimal network architecture using a deletion/substitution/addition algorithm. Results of this approach to classification are presented on simulated data and the breast cancer data of Wolberg and Mangasarian [1990. Multisurface method of pattern separation for medical diagnosis applied to breast cytology. Proc. Nat. Acad. Sci. 87, 9193–9196].  相似文献   
132.
A common task in quality control is to determine a control limit for a product at the time of release that incorporates its risk of degradation over time. Such a limit for a given quality measurement will be based on empirical stability data, the intended shelf life of the product and the stability specification. The task is particularly important when the registered specifications for release and stability are equal. We discuss two relevant formulations and their implementations in both a frequentist and Bayesian framework. The first ensures that the risk of a batch failing the specification is comparable at release and at the end of shelf life. The second is to screen out batches at release time that are at high risk of failing the stability specification at the end of their shelf life. Although the second formulation seems more natural from a quality assurance perspective, it usually renders a control limit that is too stringent. In this paper we provide theoretical insight in this phenomenon, and introduce a heat-map visualisation that may help practitioners to assess the feasibility of implementing a limit under the second formulation. We also suggest a solution when infeasible. In addition, the current industrial benchmark is reviewed and contrasted to the two formulations. Computational algorithms for both formulations are laid out in detail, and illustrated on a dataset.  相似文献   
133.
A qualitative study explored the perspectives and lived experiences of school-age children during COVID-19 using a child rights lens. Twenty children between the ages of 7 and 12 participated in open-ended, virtual interviews. Our hermeneutic analysis found children's right to play and education were severely compromised leaving children to navigate between two worlds: the adult world of public health restrictions and that of their childhood. Despite challenges and lost childhood opportunities, children emerged as competent social agents and responsible citizens. Planning for future pandemics should include policies and practices that balance public health needs with the protection of children's rights.  相似文献   
134.
Research shows that top‐down‐designed parenting programmes do not always meet the needs of postmigration parents. Bottom‐up programmes by migrant organizations hold a promise to fill this gap; however, research about these programmes and appropriate evaluation methodologies is scarce. Drawing upon Wenger's ( 2010 ) “communities of practice,” this paper explores an alternative perspective on parenting programme evaluation. Findings are presented from a study looking into social learning processes of postmigration parents who participated in a bottom‐up programme about raising teenagers in urban areas. Using an ethnographically inspired method combined with a preprogramme and postprogramme design, 115 Moroccan‐Dutch mothers and fathers from 15 programme groups participated. Results show that the programme provided a social learning space in which parents used themselves as resources to learn collectively about parenting. Moreover, parents consciously engaged in learning interactions across learning spaces stretched into their social networks. These analyses showed how parents' development of “learning citizenship” (Wenger, 2009 ) provides us with insight in collective learning dimensions present in a bottom‐up parenting programme, which is often not included in evaluation studies. Implications for practitioners as facilitators of parents' collective learning are presented.  相似文献   
135.
136.
This article addresses the connections between corporate collective action and economic development in the pre-industrial Low Countries. It focuses on a micro-historic case study: the textile industry of the village of Nieuwkerke in the county of Flanders. This rural cloth centre witnessed an exceptional industrial expansion between the fourteenth and sixteenth centuries. Following the recent proposition by Bas van Bavel that market economies follow a fixed pattern of development, the chronology of the evolution of Nieuwkerke’s cloth industry can be discussed in terms of three phases. This article argues that the first phase of development (1358–c.1500) was characterized by limited success because of pressure from the city of Ypres. The second phase (c.1500–c.1550) was marked by an industrial boom, predicated upon successful corporate collective action intertwined with the perception of social equality among the village’s cloth entrepreneurs. The third and final phase (from c.1550) was one of stagnation and decline, caused by the breaking down of the collective and concomitant social polarization. The case study thereby closely conforms to van Bavel’s theory about market cycles. Yet, the correlation between economic decline and social polarization should in this case be understood in terms of changing perceptions of inequality, rather than increasingly unequal opportunities.  相似文献   
137.
Empirical studies of ambiguity aversion often use measures that are not grounded in theory. This paper shows how a theoretically-founded measure of ambiguity aversion can be derived from Hansen and Sargent’s theory of multiplier preferences. Multiplier preferences are used in macroeconomics to capture model uncertainty. At the micro level, they have not been applied yet, because they do not permit ambiguity seeking, which is usually observed for a substantial proportion of subjects. We give a preference foundation for (extended) multiplier preferences accommodating both ambiguity aversion and ambiguity seeking and we propose a simple method to measure them using matching probabilities. We illustrate our method in two large representative samples (Dutch and American) and obtain the first micro estimates of multiplier preferences.  相似文献   
138.
This exploratory study aimed to examine which components of early childhood conscience predicted bullying involvement around school entry. In the population‐based Generation R Study, teacher reports of bullying involvement and parent reports of conscience were available for 3,244 children (M age = 6.7 years). Higher levels of overall conscience predicted lower bullying perpetration scores, independently of intelligence quotient, temperamental traits and sociodemographic characteristics. Particularly, the subscales guilt, confession, and internalized conduct, and to a lesser extent empathy, predicted bullying perpetration. Conscience was not related to victimization. Similar results were found using observations during so‐called ‘cheating games’ (subsample N = 450 children). Findings suggest that improving children's understanding of moral standards and norms may be a potential target for bullying intervention programs in early primary school.  相似文献   
139.
What role can information science play in promoting public understanding of science and technology? In order to answer this question, it is important to understand the new perspective which is emerging for research in the information science field. Internet, and the information superhighways announced both in Europe and the United States, are increasingly focusing attention on computer‐mediated communication within research communities. “Collaboratories”; is the name given to work aimed at using computer‐based technologies to help promote the social processes of knowledge production. One goal of information science lies in efforts to measure the contribution of technical devices to knowledge production practices. This is called infometrics research; it requires a clear understanding of how the social system of science regulates information flows to promote these practices.  相似文献   
140.
Socially anxiety may be related to a different pattern of facial mimicry and contagion of others’ emotions. We report two studies in which participants with different levels of social anxiety reacted to others’ emotional displays, either shown on a computer screen (Study 1) or in an actual social interaction (Study 2). Study 1 examined facial mimicry and emotional contagion in response to displays of happiness, anger, fear, and contempt. Participants mimicked negative and positive emotions to some extent, but we found no relation between mimicry and the social anxiety level of the participants. Furthermore, socially anxious individuals were more prone to experience negative emotions and felt more irritated in response to negative emotion displays. In Study 2, we found that social anxiety was related to enhanced mimicry of smiling, but this was only the case for polite smiles and not for enjoyment smiles. These results suggest that socially anxious individuals tend to catch negative emotions from others, but suppress their expression by mimicking positive displays. This may be explained by the tendency of socially anxious individuals to avoid conflict or rejection.  相似文献   
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