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1.
A dynamic network introduced by Ford and Fulkerson is a directed graph with capacities and transit times on its arcs. The quickest transshipment problem is one of the most fundamental problems in dynamic networks. In this problem, we are given sources and sinks. Then the goal of this problem is to find a minimum time limit such that we can send the right amount of flow from sources to sinks. In this paper, we introduce a variant of this problem called the mixed evacuation problem. This problem models an emergent situation in which people can evacuate on foot or by car. The goal is to organize such a mixed evacuation so that an efficient evacuation can be achieved. In this paper, we study this problem from the theoretical and practical viewpoints. In the first part, we prove the polynomial-time solvability of this problem in the case where the number of sources and sinks is not large, and also prove the polynomial-time solvability and computational hardness of its variants with integer constraints. In the second part, we apply our model to the case study of Minabe town in Wakayama prefecture, Japan.  相似文献   
2.
This study investigates the visual correspondences of gender posing behaviors, specifically exhibited by female figures, between historical European painting and contemporary American photographic advertising. While utilizing Erving Goffman’s Gender Advertisements as an analytical framework, the study focuses on the visual legacy of gender ritualization that is salient in contemporary mass media, proposing five semiotic codes to concretely analyze it. Although Goffman’s gender posing is traditionally associated with female vulnerability and indolence, the study proposes that such qualities are exploited as indicators of luxury within Western visual culture and advertising specifically. It seeks to deconstruct and re-frame the interconnected connotations of luxury and gender display, both expanding Goffman’s framework and providing a unique interpretive resource for critical readers of media texts.  相似文献   
3.
Using data from a 2011 nationally representative sample of Canadian workers (N = 5,576), the present study evaluates the social–structural determinants of the sense of mastery. Three main contributions emerge. First, we document that each of the main components of socioeconomic status—education, income, occupation, and economic hardship—have distinct total, indirect, and net associations with mastery. The well‐educated report more mastery because of their higher earnings—but exposure to more role blurring and work–family conflict offset what would otherwise be their even higher levels of mastery. Second, job‐related demands and resources have largely independent associations with mastery, but our analyses also reveal some key areas of overlap. Third, role‐blurring activities—and their connections with work‐to‐family conflict and family‐to‐work conflict—offer unique expansions to the overall narrative of mastery, with unexpected explanatory and suppression effects. We interpret each of these observations in an effort to advance recent theoretical perspectives about mastery. À partir de données recueillies en 2011 auprès d'un échantillon représentatif national de travailleurs canadiens (n = 5,576), cette étude examine les déterminants sociostructurels de la maitrise de soi. Trois principales contributions découlent de cette étude. Premièrement, chaque composante du statut socioéconomique, soit l’éducation, le revenu, la profession de même que la précarité économique, a une association distincte et indirecte avec la maitrise de soi. Par exemple, les travailleurs instruits ressentent un plus grand sentiment de maitrise de soi dû à leur revenu supérieur. Toutefois, l'ambigüité de rôle et le conflit travail‐famille, plus fréquents chez ces derniers, atténuent cette relation. Deuxièmement, les demandes et les ressources liées au travail sont indirectement associées avec la maitrise de soi. Cependant, nos analyses démontrent que certains secteurs importants se chevauchent. Troisièmement, les liens entre les secteurs d'activités pour lesquelles il y a ambigüité de rôle et les conflits travail‐famille et les conflits famille‐travail permettent de mieux comprendre le concept de maitrise de soi chez les travailleurs canadiens. Nos analyses démontrent des effets inattendus explicatifs et de suppression. Nous interprétons chacune des ces observations en vue de faire avancer les perspectives théoriques récentes en ce qui a trait à la maitrise de soi.  相似文献   
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Since the end of 1990s, approximately 160 million Chinese rural workers migrated to cities for work. Because of restrictions on migrant access to local health and education systems, many rural children are left behind in home villages to grow up without parental care. This article examines how exposure to cumulative parental migration affects children’s health and education outcomes. Using the Rural-Urban Migration Survey in China (RUMiC) data, we measure the share of children’s lifetime during which parents were away from home. We instrument this measure of parental absence with weather changes in their home villages when parents were aged 16–25, when they were most likely to initiate migration. Results show a sizable adverse effect of exposure to parental migration on the health and education outcomes of children: in particular, boys. We also find that the use of the contemporaneous measure for parental migration in previous studies is likely to underestimate the effect of exposure to parental migration on children’s outcomes.  相似文献   
6.
This paper examines the nonmarket interactions among migrants in the urban labor market of Bangkok, Thailand. We test whether the population size and the labor-market performance of previous migrants have externalities to new migrants who have moved from the same province of origin. Our empirical results, which control origin fixed effects, time fixed effects, and origin- and year-specific correlated shocks, show that (1) the relative population size of previous migrants in the market decreases the employment probability of new migrants (substitution effect), (2) the employment probability of previous migrants increases that of new migrants (positive externalities), and (3) when the employment probability of previous migrants is high, however, the scale effect becomes positive, which demonstrates a threshold in the informational scale economies. The results imply that positive informational scale effect dominates negative substitution effect when the efficiency of previous migrants is sufficiently high in the destination labor market.
Futoshi YamauchiEmail:
  相似文献   
7.
This paper questions whether personal income comparison explains the distributive gap between income and class identification by exploring the following two issues: empirical validity of income comparison as the determinant of class identification, and theoretical validity of income comparison for the distributive gap. For the first issue, we conduct a statistical analysis using data from the Social Stratification and Social Mobility surveys (1975–2005), and the Stratification and Social Psychology-I survey (2010). We find that the criteria for choosing reference groups changed historically from residential proximity to occupational equality. In addition, income comparison with sensitive to lower-income possessors and a distorted perception of income difference significantly affected class identification, except for the year of 1985. The simulation analysis employed to examine the second issue clarified that income comparison with the above-mentioned features yields a less skewed distribution compared to that of class identification. The data also indicates that the empirical conditions of income are satisfied for realization of this result. Thus, we could ascertain empirical and theoretical validity of income comparison as explanation for the distributive gap between income and class identification.  相似文献   
8.
This article proposes new methodologies for evaluating economic models’ out-of-sample forecasting performance that are robust to the choice of the estimation window size. The methodologies involve evaluating the predictive ability of forecasting models over a wide range of window sizes. The study shows that the tests proposed in the literature may lack the power to detect predictive ability and might be subject to data snooping across different window sizes if used repeatedly. An empirical application shows the usefulness of the methodologies for evaluating exchange rate models’ forecasting ability.  相似文献   
9.
It is widely known that significant in-sample evidence of predictability does not guarantee significant out-of-sample predictability. This is often interpreted as an indication that in-sample evidence is likely to be spurious and should be discounted. In this paper, we question this interpretation. Our analysis shows that neither data mining nor dynamic misspecification of the model under the null nor unmodelled structural change under the null are plausible explanations of the observed tendency of in-sample tests to reject the no-predictability null more often than out-of-sample tests. We provide an alternative explanation based on the higher power of in-sample tests of predictability in many situations. We conclude that results of in-sample tests of predictability will typically be more credible than results of out-of-sample tests.  相似文献   
10.
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