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41.
In 2015, the United Nations (UN) issued probabilistic population projections for all countries up to 2100, by simulating future levels of total fertility and life expectancy and combining the results using a standard cohort component projection method. For the 40 countries with generalized HIV/AIDS epidemics, the mortality projections used the Spectrum/Estimation and Projection Package (EPP) model, a complex, multistate model designed for short-term projections of policy-relevant quantities for the epidemic. We propose a simpler approach that is more compatible with existing UN projection methods for other countries. Changes in life expectancy are projected probabilistically using a simple time series regression and then converted to age- and sex-specific mortality rates using model life tables designed for countries with HIV/AIDS epidemics. These are then input to the cohort component method, as for other countries. The method performed well in an out-of-sample cross-validation experiment. It gives similar short-run projections to Spectrum/EPP, while being simpler and avoiding multistate modelling.  相似文献   
42.
Traditionally at the margins of the political debate, minimum income protection has recently become a key issue in Italian politics. After decades of social and political “neglect” letting Italy the only European country (with Greece) still lacking an anti-poverty minimum income safety net in the 2010s, finally a national programme called Inclusion Income was introduced in 2018, then replaced by a more robustly financed scheme, the Citizenship Income in 2019. The introduction of these new programmes was the object of an intense political debate, which raises two main puzzles. Why a policy field characterized by the low political resources of would be beneficiaries and low incidence on the overall welfare budget has become so important in the political debate? How did it occur in Italy, where minimum income protection had been absent in political discourses for at least five decades after World War II? To answer these questions, this article first elaborates a novel theoretical framework which combines the main properties of socio-political demand and political supply in order to explain the scope and direction of minimum income reforms. Second, it provides an analytically oriented reconstruction of MIS policy trajectory in Italy in the three different phases: the phase of MIS “neglect” (1948–1992) characterized by inertia; the period of political “contentiousness” (1993–2012), marked by attempts of path departure followed by policy reversals; the more recent phase leading to the introduction and institutionalization of a MIS. Third, the article provides a theoretically framed interpretation of the overall MIS trajectory in Italy.  相似文献   
43.
日语空间性状的时间映射具有局部映射性和选择性,映射具有负向语义选择偏好;形成“水平线性空间>垂直线性空间>立体三维空间”维度制约等级。上述制约特质是时空隐喻概念相似性与语言类型特质共同驱动促成的。概念相似性是其内在驱动力,相似者易于映射,反之则受制约性强;日语的时间性特质是其负向语义选择偏好的外在驱动力。  相似文献   
44.
Care occupations are gendered and remain relatively poorly paid, particularly in the United States. Prior research on the ‘care penalty’ primarily points to individual, relational, and market-valuation factors in explaining the relative earnings of care workers. This study integrates these explanations with a comparative institutional perspective. Using higher-quality data and methods than previous comparative research in the field—that is, harmonized micro-data from the Current Population Survey and EU-SILC from 2005 to 2016, country and year fixed effects models, and a counterfactual analysis—we find that national variance in labour market and welfare state institutions explains most of the difference in the relative earnings of reproductive care workers between the United States and European countries. Higher rates of collective bargaining coverage, stronger employment protection and welfare state spending contribute to higher relative earnings for reproductive care occupations, and lower relative earnings for high-status nurturant care occupations. Differences in the relative earnings of care workers appear to be mostly a construct of social policy and labour market institutions rather than individual, relational, and market-valuation factors.  相似文献   
45.
I discuss the revolutionary implications of Alexander Wendt's Quantum Mind and Social Science for social theory. These center on the significance given to society as a possibility space in which observable social reality amounts to quantum decoherent states in the system. I discuss how Wendt radicalises social constructivism and goes considerably beyond Bourdieu's conceptions of society as a field. A signature feature in Wendt's theory, the state as a hologram, comports well with the implied view of the social order in much public opinion and market research. In this respect, Wendt's theory is very attuned to the spirit of our times.  相似文献   
46.
In this paper, we present an algorithm for clustering based on univariate kernel density estimation, named ClusterKDE. It consists of an iterative procedure that in each step a new cluster is obtained by minimizing a smooth kernel function. Although in our applications we have used the univariate Gaussian kernel, any smooth kernel function can be used. The proposed algorithm has the advantage of not requiring a priori the number of cluster. Furthermore, the ClusterKDE algorithm is very simple, easy to implement, well-defined and stops in a finite number of steps, namely, it always converges independently of the initial point. We also illustrate our findings by numerical experiments which are obtained when our algorithm is implemented in the software Matlab and applied to practical applications. The results indicate that the ClusterKDE algorithm is competitive and fast when compared with the well-known Clusterdata and K-means algorithms, used by Matlab to clustering data.  相似文献   
47.
When sampling from a continuous population (or distribution), we often want a rather small sample due to some cost attached to processing the sample or to collecting information in the field. Moreover, a probability sample that allows for design‐based statistical inference is often desired. Given these requirements, we want to reduce the sampling variance of the Horvitz–Thompson estimator as much as possible. To achieve this, we introduce different approaches to using the local pivotal method for selecting well‐spread samples from multidimensional continuous populations. The results of a simulation study clearly indicate that we succeed in selecting spatially balanced samples and improve the efficiency of the Horvitz–Thompson estimator.  相似文献   
48.
This study develops a robust automatic algorithm for clustering probability density functions based on the previous research. Unlike other existing methods that often pre-determine the number of clusters, this method can self-organize data groups based on the original data structure. The proposed clustering method is also robust in regards to noise. Three examples of synthetic data and a real-world COREL dataset are utilized to illustrate the accurateness and effectiveness of the proposed approach.  相似文献   
49.
The Hodrick–Prescott (HP) filtering is frequently used in macroeconometrics to decompose time series, such as real gross domestic product, into their trend and cyclical components. Because the HP filtering is a basic econometric tool, it is necessary to have a precise understanding of the nature of it. This article contributes to the literature by listing several (penalized) least-squares problems that are related to the HP filtering, three of which are newly introduced in the article, and showing their properties. We also remark on their generalization.  相似文献   
50.
卫星导航定位是测绘工程中发展较快、应用较广的一项热门技术,“GPS测量与数据处理”课程也一直是测绘专业本科教学的主干课程,具有更新快、理论深、实践性强等特点,对教师授课及学生学习都具有较高的要求。文章对东华理工大学测绘工程专业GPS课程的授课内容、授课方式、实践教学及考核模式等方面存在的问题进行了分析,并提出了相应的教学改革建议。  相似文献   
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