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141.
This article describes research on fishermen's health and sleeping habits in Iceland. It presents the first findings of the project that were presented in October 2002 at a conference that was organized during Seamen Safety Week in Iceland. It covers physical and mental stress symptoms, sleep disturbance, and obesity, as well as fishermen's own reaction to their health and well-being. Take notice that the findings that are presented in this article can be found in a report presented in August, when the whole study will be finished. Finally, it is concluded how successful the response has been and how the project can be used positively with other studies. It is also noted that, in fact, these findings will be used for further studies linked to safety on board.  相似文献   
142.
Research on disparities in health and services should include a critical examination of how social, cultural, and contextual factors affect the connection between symptoms and psychiatric disorders. Systematic differences in this connection by these factors will mean that clinicians using a universalist approach to disorders may make more diagnostic errors for certain patients (e.g., ethnic minorities, the poor). Based on the literature on normative clinical decision-making, this study tests for whether the effect of specific psychiatric disorders on key symptoms is the same for certain groups of the population. The data come from the National Comorbidity Survey. Conditional probabilities of disorders and symptoms, the elements feeding into clinical decision-making, are calculated and tested for equivalence across various racial/ethnic, educational, income, and gender groups. We find some significant differences in the relation of key symptoms to disorders across groups. These findings should encourage testing relativistic frameworks in diagnostic nosology as a step to improve clinical decision-making and reduce diagnostic and treatment disparities in mental health services.  相似文献   
143.
Literature on ambidexterity emphasizes the need for both exploration and exploitation. Large firms usually choose to implement structural ambidexterity to separate both activities. We here focus on an extreme case of such structural partitioning implemented as a secret skunkworks project in a large French automotive company. A qualitative survey using both primary and secondary data shows that the major basic and initial characteristics of a skunkworks (i.e. secrecy, urgency, and autonomy) created favorable conditions for the technological exploration. However, exploitation failed due to precisely those same characteristics coupled with the fact that the project did not respond to a specific market demand: The skunkworks suffered from what we call the "Robinson Crusoe effect." We therefore contribute to the literature on skunkworks, which have remained understudied in the academic literature, as well as on ambidexterity, by showing how the interrelation between different factors is crucial for structural ambidexterity to be successful  相似文献   
144.
The main models of machine learning are briefly reviewed and considered for building a classifier to identify the Fragile X Syndrome (FXS). We have analyzed 172 patients potentially affected by FXS in Andalusia (Spain) and, by means of a DNA test, each member of the data set is known to belong to one of two classes: affected, not affected. The whole predictor set, formed by 40 variables, and a reduced set with only nine predictors significantly associated with the response are considered. Four alternative base classification models have been investigated: logistic regression, classification trees, multilayer perceptron and support vector machines. For both predictor sets, the best accuracy, considering both the mean and the standard deviation of the test error rate, is achieved by the support vector machines, confirming the increasing importance of this learning algorithm. Three ensemble methods - bagging, random forests and boosting - were also considered, amongst which the bagged versions of support vector machines stand out, especially when they are constructed with the reduced set of predictor variables. The analysis of the sensitivity, the specificity and the area under the ROC curve agrees with the main conclusions extracted from the accuracy results. All of these models can be fitted by free R programs.  相似文献   
145.
In this article, we explore the impacts that education expansion and increased levels in educational homogamy have had on couples’ isolated illiteracy rates, defined as the proportion of illiterates in union that are married to an illiterate partner. First, we develop the methodology to decompose isolated illiteracy rates into two main components: one related to level of homogamy among illiterates, and the other related to the educational distribution of the spouses. Second, we use harmonized international census microdata from IPUMS and DHS data for 73 countries and 217 samples to investigate which of the two components is more important in shaping the level of isolated illiteracy. Our results indicate that the expansion of literacy has been more powerful than the increases in the tendency toward homogamy in its impact on isolated illiteracy rates. As the percentage of illiterates decreases over time, an increasingly large proportion of them marry literate individuals, showing that opportunities for intermarriage among illiterates expand despite the strengthening of homogamy.  相似文献   
146.
A prevalence of heavy-tailed, peaked and skewed uncertainty phenomena have been cited in literature dealing with economic, physics, and engineering data. This fact has invigorated the search for continuous distributions of this nature. In this paper we shall generalize the two-sided framework presented in Kotz and van Dorp (Beyond beta: other continuous families of distributions with bounded support and applications. World Scientific Press, Singapore, 2004) for the construction of families of distributions with bounded support via a mixture technique utilizing two generating densities instead of one. The family of Elevated Two-Sided Power (ETSP) distributions is studied as an instance of this generalized framework. Through a moment ratio diagram comparison, we demonstrate that the ETSP family allows for a remarkable flexibility when modeling heavy-tailed and peaked, but skewed, uncertainty phenomena. We shall demonstrate its applicability via an illustrative example utilizing 2008 US income data.  相似文献   
147.
A qualitative study was carried out in four municipalities in four different conflict zones in Colombia. Intrafamilial violence and gender violence are studied through the testimonies of the people interviewed. The impact was analysed in terms of the exercise of control over the civilian population by paramilitaries in relation to subjectivity, the family, social networks and the prevailing moral order. In effect, the strengthening of barriers between traditional gender identities has enabled a de-structuring of traditional masculinity through moral co-optation, the reinforcement of traditional feminine identity and the objectification of the sexuality of young women, at the same time as they are manipulated sexually and emotionally. In general, strong legitimation of the model of the armed fighter as a paradigm of masculinity is found in children. In addition, the de-structuring of the family and its manipulation as a means of influence over civil society is one of the strategies employed for the installation of a regime of terror that fractures social networks. It does this through the erosion of confidence and the legitimation and mystification of the power of an actor whose mediation in inter-family and micro-social conflicts has been legitimated, instrumentalizing and scaling up traditional violence, taking advantage of the power vacuum and moral weaknesses in local culture.  相似文献   
148.
This paper provides an analysis of the Minimal Overlap Rule, a solution for bankruptcy problems introduced by O’Neill (1982). We point out that this rule can be understood as a composition of Ibn Ezra’s proposal and the recommendation given by the Constrained Equal Loss Rule. Following an interpretation of bankruptcy problems in terms of TU games, we show that the Minimal Overlap Value is the unique solution for bankruptcy games which satisfies Anonymity and Core Transition Responsiveness.  相似文献   
149.
In this paper we consider the Capital Asset Pricing Model under Elliptical (symmetric) Distributions. This class of distributions, which contains the normal distribution, t, contaminated normal and power exponential, among others, offers a more flexible framework for modelling asset prices or returns. In order to analyze the sensibility to possible outliers and/or atypical returns of the maximum likelihood estimators, the local influence method was implemented. The results are illustrated by using a set of shares from companies who trade in the Chilean Stock Market. Our main conclusion is that symmetric distributions having heavier tails than those of the normal distribution, especially the t distribution with small degrees of freedom, show a better fit and allow the reduction of the influence of atypical returns in the maximum likelihood estimators.  相似文献   
150.
During the last few years, changes in the Spanish educational system have had a far reaching impact. Several factors have been critical: (1) the progressive decentralization of education by the government, now a responsibility of regional governments; (2) the extension of compulsory education to the age of 16; and finally (3) the increase in the number of immigrant students, which has significantly added to the existing cultural diversity. The enrolment of immigrant students in Spanish schools is a relatively recent phenomenon (starting 15 years ago) when compared with other European countries. Madrid is the region in Spain with the largest number of students. As most of these students were born outside of Spain, we cannot yet speak of a second generation. The research described here investigated how the educational system in Madrid confronted the challenge of an increasing number of immigrant students. The institutional response was the Madrid Regional Government’s Compensatory Education Regional Plan. This encompasses several measures, which are described here. After a critical analysis of educational policies pertaining to immigrant pupils, the paper suggests ways of overcoming a purely compensatory approach. Intercultural education plays a key role is such considerations.  相似文献   
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