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1.
The study reported describes Efe (pygmy) forager one-, two-, and three-year-olds' involvement with males. The Efe of northeastern Zaïre were chosen because their social organization allows us to examine hypotheses based on studies in Western, technologically complex societies about the distinctive role fathers play in the lives of their young children. Behavioral observations of Efe children's day-to-day activities with fathers, men and boys were recorded using a focal subject sampling technique (Altmann, 1974). Two behavioral measures were created to capture the extent to which males were involved with children: Social engagement describes males' involvement with children and social attention describes eavesdropping by children on males' everyday activities. Eight one-year-olds, 7 two-year-olds and 8 three-year-olds were each observed for six, one-hour observation sessions that were distributed evenly over the daylight hours. Data were analyzed using the traditional measure of involvement (e.g., adult males) and using a newly developed measure of the involvement of the average individual (e.g., average adult mate). Comparisons at each of the ages showed that fathers were consistently like other men in the extent to which children participated in social activities with them and watched their activities. Only fathers' level of social engagement declined significantly as children grew older. Boys' role relative to other males became increasingly distinctive as children aged. The findings suggest that Efe fathers may not be unique in the same sense assumed by Western study ideals, and raise questions about the special status given to fathers in Western theory and data. The patterning of mate involvement with children is discussed in terms of Efe community life, and in terms of Efe children's developing understanding of their relationship with fathers and other males.  相似文献   
2.
This paper examines the response of income concentration in the US to the occurrence of major systemic banking crises since the beginning of the twentieth century. In doing so, the paper analyzes the shape of the upper income tail as well as the national income shares accruing to different groups within the richest decile. The findings suggest that systemic banking crises reduce income concentration within the top decile of the US pre–tax and transfers income distribution, and more generally, that the effect is highly heterogeneous across different top income groups. While the richest income group loses ground, the lower half of the top decile appears to gain in relative terms. However, evidence suggests that the estimated short-term effect of market forces stemming from banking crises can be relatively small in magnitude and even temporary in nature, as it may be quickly reabsorbed. These findings lend indirect support to the idea that only substantial changes in government policies and institutional frameworks can bring about radical changes in income distribution.  相似文献   
3.
Despite recent strong interest in the link between fertility and subjective well-being, the focus has centered on developed countries. For poorer countries, in contrast, the relationship remains rather elusive. Using a well-established panel survey—the Ethiopian Rural Household Survey (ERHS)—we investigate the empirical relationship between fertility and life satisfaction in rural Ethiopia, the largest landlocked country in Africa. Consistent with the fertility theories for developing countries and with the sociodemographic characteristics of rural Ethiopia, we hypothesize that this relationship varies by gender and across life stages, being more positive for men and for parents in old age. Indeed, our results suggest that older men benefit the most in terms of life satisfaction from having a large number of children, while the recent birth of a child is detrimental for the subjective well-being of women at reproductive ages. We address endogeneity issues by using lagged life satisfaction in ordinary least squares regressions, through fixed-effects estimation and the use of instrumental variables.  相似文献   
4.
The increased frequency of extreme events in recent years highlights the emerging need for the development of methods that could contribute to the mitigation of the impact of such events on critical infrastructures, as well as boost their resilience against them. This article proposes an online spatial risk analysis capable of providing an indication of the evolving risk of power systems regions subject to extreme events. A Severity Risk Index (SRI) with the support of real‐time monitoring assesses the impact of the extreme events on the power system resilience, with application to the effect of windstorms on transmission networks. The index considers the spatial and temporal evolution of the extreme event, system operating conditions, and the degraded system performance during the event. SRI is based on probabilistic risk by condensing the probability and impact of possible failure scenarios while the event is spatially moving across a power system. Due to the large number of possible failures during an extreme event, a scenario generation and reduction algorithm is applied in order to reduce the computation time. SRI provides the operator with a probabilistic assessment that could lead to effective resilience‐based decisions for risk mitigation. The IEEE 24‐bus Reliability Test System has been used to demonstrate the effectiveness of the proposed online risk analysis, which was embedded in a sequential Monte Carlo simulation for capturing the spatiotemporal effects of extreme events and evaluating the effectiveness of the proposed method.  相似文献   
5.
This paper studies the role of different types of credit institutions in income inequality. By analyzing Italian local (provincial) credit markets over the 2001–2011 period, we find that cooperative banks mitigate income inequality in local communities more than their commercial counterparts. The results also suggest that it is the specific nature and orientation of cooperative banks, more than their relationship lending technologies, that improve income distribution. The impact of cooperative banking on inequality appears however to be partly channeled by a reduced dynamism of local economies, especially lower migratory flows and business turnover. (JEL G21, G38, O15)  相似文献   
6.

The purpose of this paper is to show in regression clustering how to choose the most relevant solutions, analyze their stability, and provide information about best combinations of optimal number of groups, restriction factor among the error variance across groups and level of trimming. The procedure is based on two steps. First we generalize the information criteria of constrained robust multivariate clustering to the case of clustering weighted models. Differently from the traditional approaches which are based on the choice of the best solution found minimizing an information criterion (i.e. BIC), we concentrate our attention on the so called optimal stable solutions. In the second step, using the monitoring approach, we select the best value of the trimming factor. Finally, we validate the solution using a confirmatory forward search approach. A motivating example based on a novel dataset concerning the European Union trade of face masks shows the limitations of the current existing procedures. The suggested approach is initially applied to a set of well known datasets in the literature of robust regression clustering. Then, we focus our attention on a set of international trade datasets and we provide a novel informative way of updating the subset in the random start approach. The Supplementary material, in the spirit of the Special Issue, deepens the analysis of trade data and compares the suggested approach with the existing ones available in the literature.

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7.
8.
This paper investigates the media’s role in shaping perceptions and policies concerning the so-called migrant crisis as well as how this affects solidarity with newcomers, specifically focusing on Italy. The first part of the paper examines the coexistence of the humanitarian narratives of saving lives and the spectacle of militarised borders. It unveils how the daily transmission of sensationalist and stereotyped images of migrants contributes to their transforming into subjects and objects of fear, both experiencing the fear of being rejected and eliminated and inspiring fear in the resident populations. The second part addresses the need for innovative approaches in the construction of a positive public image of migrants and refugees. Through an analysis of several communication campaigns, realised by state and non-state actors for the promotion of social coexistence between citizens and newcomers, this paper calls for a fundamental shift in the way we communicate about migration. A concluding reflection on the challenges and opportunities posed by the arrival of migrants and asylum seekers in our societies, proposes that they should not only be perceived as objects of policies, but should be considered active partners of their own inclusion in the receiving societies.  相似文献   
9.
On Approximating a Scheduling Problem   总被引:4,自引:0,他引:4  
Given a set of communication tasks (best described in terms of a weighted bipartite graph where one set of nodes denotes the senders, the other set the receivers, edges are communication tasks, and the weight of an edge is the time required for transmission), we wish to minimize the total time required for the completion of all communication tasks assuming that tasks can be preempted (that is, each edge can be subdivided into many edges with weights adding up to the edge's original weight) and that preemption comes with a cost. In this paper, we first prove that one cannot approximate this problem within a factor smaller than unless P=NP. It is known that a simple approximation algorithm achieves within a ratio of two (H. Choi and S.L. Hakimi, Algorithmica, vol. 3, pp. 223–245, 1988). However, our experimental results show that its performance is worse than the originally proposed heuristic algorithm (I.S. Gopal and C.K. Wong, IEEE Transactions on Communications, vol. 33, pp. 497–501, 1985). We devise a more sophisticated algorithm, called the potential function algorithm which, on the one hand, achieves a provable approximation ratio of two, and on the other hand, shows very good experimental performance. Moreover, the way in which our more sophisticated algorithm derives from the simple one, suggests a hierarchy of algorithms, all of which have a worst-case performance at most two, but which we suspect to have increasingly better performance, both in worst case and with actual instances.  相似文献   
10.
At the time of the financial crises of 2008 and 2010–11 the ECB reacted with an extremely cautious gradualism. This behaviour is attributable to the slower learning process that characterizes a central bank of a monetary union composed of countries with fiscal sovereignty compared to other central banks. In sharp contrast to the previous crises, the ECB reacted promptly to the COVID-19 crisis. This change in behaviour is explained here by the learning process about the effects on monetary policy transmission of the increased financial fragmentation of the eurozone over the last decade.  相似文献   
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