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101.
We propose the use of signal detection theory (SDT) to evaluate the performance of both probabilistic forecasting systems and individual forecasters. The main advantage of SDT is that it provides a principled way to distinguish the response from system diagnosticity, which is defined as the ability to distinguish events that occur from those that do not. There are two challenges in applying SDT to probabilistic forecasts. First, the SDT model must handle judged probabilities rather than the conventional binary decisions. Second, the model must be able to operate in the presence of sparse data generated within the context of human forecasting systems. Our approach is to specify a model of how individual forecasts are generated from underlying representations and use Bayesian inference to estimate the underlying latent parameters. Given our estimate of the underlying representations, features of the classic SDT model, such as the receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC), follow immediately. We show how our approach allows ROC curves and AUCs to be applied to individuals within a group of forecasters, estimated as a function of time, and extended to measure differences in forecastability across different domains. Among the advantages of this method is that it depends only on the ordinal properties of the probabilistic forecasts. We conclude with a brief discussion of how this approach might facilitate decision making.  相似文献   
102.
Land subsidence risk assessment (LSRA) is a multi‐attribute decision analysis (MADA) problem and is often characterized by both quantitative and qualitative attributes with various types of uncertainty. Therefore, the problem needs to be modeled and analyzed using methods that can handle uncertainty. In this article, we propose an integrated assessment model based on the evidential reasoning (ER) algorithm and fuzzy set theory. The assessment model is structured as a hierarchical framework that regards land subsidence risk as a composite of two key factors: hazard and vulnerability. These factors can be described by a set of basic indicators defined by assessment grades with attributes for transforming both numerical data and subjective judgments into a belief structure. The factor‐level attributes of hazard and vulnerability are combined using the ER algorithm, which is based on the information from a belief structure calculated by the Dempster‐Shafer (D‐S) theory, and a distributed fuzzy belief structure calculated by fuzzy set theory. The results from the combined algorithms yield distributed assessment grade matrices. The application of the model to the Xixi‐Chengnan area, China, illustrates its usefulness and validity for LSRA. The model utilizes a combination of all types of evidence, including all assessment information—quantitative or qualitative, complete or incomplete, and precise or imprecise—to provide assessment grades that define risk assessment on the basis of hazard and vulnerability. The results will enable risk managers to apply different risk prevention measures and mitigation planning based on the calculated risk states.  相似文献   
103.
In a series of major papers culminating in A Theory of Justice, John Rawls constructs an alternative to utilitarianism by developing a social contract theory of moral and political philosophy. Unfortunately, Rawls formulates the two basic principles upon which the theory rests in such a way as to restrict (unduly) the contract theory's applicability (see Section I). In this paper we present a more general discussion of the theory of justice that avoids the problems of Rawls' formulation and yet retains the important idea of justice as fairness and the contractarian approach (Section II). Later it is argued that this more general theory constitutes a bridge between the pure utilitarian theories and the social contract doctrines (Sections V and VI). The theory's advantages are demonstrated by applying it to a problem discussed by Rawls, intergenerational equity, and comparing the two solutions (Section III). Further comparisons are made and inferences drawn in the concluding three sections.Without implicating them, we would like to thank James M. Buchanan and David Lyons for comments on an earlier draft of this paper.
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104.
We set out to explore the meaning of the attachment categories in the Cassidy/Marvin strange situation procedure, as employed in the home, using data from a longitudinal study of children adopted into UK families up to the age of 42 months from Romanian institutions, and of adopted children without the experience of institutional care––both groups being assessed at 4 and 6 years of age. Inter‐rater reliability was found to be good. Security (meaning the use of the parent as a secure base and no negative behavior on reunion) was the modal categorical rating in both the institution‐reared and comparison groups, but the category of anomalous non‐normative behavior (meaning a lack of any ordered attachment behavior as covered by the standard ratings), previously labeled ‘insecure‐other’, was more common in the institution‐reared children. Because this was unassociated with the usual manifestations of insecurity (such as avoidance or resistance) and because it was largely evident in interactions with the stranger, it is concluded that the adjective ‘insecure’ was not appropriate. Although this ‘insecure‐other’ category was associated with disinhibited attachment as reported by parents (meaning a lack of differentiation among adults, a willingness to go off with strangers and a lack of checking back with parents in anxiety‐provoking situations), it did not prove to be a good index of disinhibited attachment because changes over time in the ‘insecure‐other’ category were not associated with changes in the rate of disinhibited attachment. Also, whereas the rate of ‘insecure‐other’ fell markedly in the institution‐reared group between 4 and 6 years of age, it rose in the comparison group, raising queries over its meaning.  相似文献   
105.
We examine differences in the value of statistical life (VSL) across potential wage levels in panel data using quantile regressions with intercept heterogeneity. Latent heterogeneity is econometrically important and affects the estimated VSL. Our findings indicate that a reasonable average cost per expected life saved cut-off for health and safety regulations is 7 million to7 million to 8 million per life saved, but the VSL varies considerably across the labor force. Our results reconcile the previous discrepancies between hedonic VSL estimates and the values implied by theories linked to the coefficient of relative risk aversion. Because the VSL varies elastically with income, regulatory agencies should regularly update the VSL used in benefit assessments, increasing the VSL proportionally with changes in income over time.  相似文献   
106.
Right in Amsterdam’s picturesque Canal Zone, on and around Zeedijk, Chinese entrepreneurs have carved out a presence in what seems like the local Chinatown. The businessmen have been targeting Asian and non-Asian customers by offering products that – to an extent – can be associated with Asia, China in particular. Since the early 1990s, individual entrepreneurs and their business organisations have campaigned for official acknowledgement of Zeedijk as an ethnic-only district and for governmental support of the enhancement of Chineseness. Following Hackworth and Rekers. [(2005). “Ethnic Packaging and Gentrification. The Case of Four Neighborhoods in Toronto.” Urban Affairs Review 41 (2): 211–236], we argue that this case challenges traditional understandings of ethnic commercial landscapes. In sharp contrast to the current orthodoxy, which would conceive the proliferation of such an ‘ethnic enclave’ as part of a larger process of assimilation, we have approached Amsterdam’s Chinatown first and foremost as a themed economic space: Chinese and other entrepreneurs compete for a share of the market and in doing also for the right to claim the identity of the area. What is the historical development of the Zeedijk area, how did Chinese entrepreneurs and their associations try to boost Chinatown and negotiate public Chineseness, and how did governmental and non-governmental institutional actors respond to those attempts?  相似文献   
107.
Perceived racial discrimination (PRD) has been implicated in undermining the mental and physical health of racial/ethnic minorities (e.g., Williams et al. in Am J Public Health 93:200–208, 2003; Wong et al. in J Pers 71:1197–1232, 2003). Researchers have begun to explore the indirect role of health behaviors as one factor in helping to explain this relationship. The goal of the present study was to examine the relationship between PRD and a wide range of health behaviors using a prospective, longitudinal design and to explore the role of gender in moderating these relationships. Using data from the Maryland Adolescent Development in Context Study, we examined the relationship between adolescent PRD (accumulated across ages 14–21) and health behaviors (i.e., diet, substance use, exercise) at age 30 in a sample of middle-class black men and women. Using structural equation modeling, results revealed that more cumulative PRD during adolescence was associated with less healthy eating, more substance use (among men), and more exercise (among women) in young adulthood. Implications of these findings for understanding the role of health behaviors in explaining the link between PRD and health outcomes are considered.  相似文献   
108.
109.
People often express excitement to each other when encountering an object that they have shared together previously in some special way. This study investigated whether 14‐month‐old infants know precisely what they have and have not shared in a special way (and with whom). In the experimental condition an adult and infant shared an object (the target) excitedly because it unexpectedly reappeared in several places. They then shared 2 other objects (the distractors) in a more normal fashion. Later, the adult reacted excitedly to a tray containing all 3 objects and then made an ambiguous request for the infant to hand “it” to her. There were 2 control conditions. In 1 of them, a different adult, who knew none of the 3 objects, made the ambiguous request. In the other control condition, the adult who made the request had previously experienced the objects only alone, while the infant looked on unengaged. Infants in the experimental condition chose the target object more often than the distractors and more often than they chose it in either control condition. These results demonstrate that 14‐month‐old infants can identify which one of a set of objects “we”—and not just I or you alone—have had a special experience with in the past.  相似文献   
110.
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