This article studies the dominance solvability (by iterated deletion of weakly dominated strategies) of general scoring rule voting games when there are three alternatives. The scoring rules we study include Plurality rule, Approval voting, Borda rule, and Relative Utilitarianism. We provide sufficient conditions for dominance solvability of general scoring rule voting games. The sufficient conditions that we provide for dominance solvability are in terms of one statistic of the game: sufficient agreement on the best alternative or on the worst alternative. We also show that the solutions coincide with the set of Condorcet Winners whenever the sufficient conditions for dominance solvability are satisfied. Approval Voting performs the best in terms of our criteria. 相似文献
Housing affordability is a complex issue that must not only be assessed in terms economic viability. In order to increase quality of life and community sustainability the environmental and social sustainability of housing must also be taken into consideration. 相似文献
Using 30 years of longitudinal data from a nationally representative cohort of women, we study the association between breastfeeding duration and completed fertility, fertility expectations, and birth spacing. We find that women who breastfeed their first child for five months or longer are a distinct group. They have more children overall and higher odds of having three or more children rather than two, compared with women who breastfeed for shorter durations or not at all. Expected fertility is associated with initiating breastfeeding but not with how long mothers breastfeed. Thus, women who breastfeed longer do not differ significantly from other breastfeeding women in their early fertility expectations. Rather, across the life course, these women achieve and even exceed their earlier fertility expectations. Women who breastfeed for shorter durations (1–21 weeks) are more likely to fall short of their expected fertility than to achieve or exceed their expectations, and they are significantly less likely than women who breastfeed for longer durations (≥22 weeks) to exceed their expected fertility. In contrast, women who breastfeed longer are as likely to exceed as to achieve their earlier expectations, and the difference between their probability of falling short versus exceeding their fertility expectations is relatively small and at the boundary of statistical significance (p = .096). These differences in fertility are not explained by differences in personal and family resources, including family income or labor market attachment. Our findings suggest that breastfeeding duration may serve as a proxy for identifying a distinct approach to parenting. Women who breastfeed longer have reproductive patterns quite different than their socioeconomic position would predict. They both have more children and invest more time in those children. 相似文献
In the 1-in port model, every vertex of a synchronous network can receive at most one message in each time unit. We consider simultaneous broadcasting of multiple messages from the same source or from distinct sources in such networks with an additional restriction that every received message can be sent out to neighbors only in the next time unit and never to already informed vertex. We use a general concept of level-disjoint partitions developed for this scenario. Here we introduce a subgraph extension technique for efficient spreading information within this concept. Surprisingly, this approach with so called biwheels leads to simultaneous broadcasting of optimal number of messages on a wide class of graphs in optimal time. In particular, we provide tight results for bipartite tori, meshes, hypercubes, Knödel graphs, circulant graphs. We also propose several open problems and conjectures. 相似文献
Many studies from developed countries show a negative correlation between family size and children’s schooling, while results
from developing countries show this association ranging from positive to neutral to negative, depending on the context. The
body of evidence suggests that this relationship changes as a society develops, but this theory has been difficult to assess
because the existing evidence requires comparisons across countries with different social structures and at different levels
of development. The world’s fourth most populous nation in 2007, Indonesia has developed rapidly in recent decades. This context
provides the opportunity to study these relationships within the same rapidly developing setting to see if and how these associations
change. Results show that in urban areas, the association between family size and children’s schooling was positive for older
cohorts but negative for more recent cohorts. Models using instrumental variables to address the potential endogeneity of
fertility con rm these results. In contrast, rural areas show no significant association between family size and children’s
schooling for any cohort. These findings show how the relationship between family size and children’s schooling can differ
within the same country and change over time as contextual factors evolve with socioeconomic development. 相似文献
This article initiates a Sociology of Security. Such a field should analyze how conditions transpire for security—however defined—to surface as a value in individual and collective living, how this value comes to be articulated, and how different kinds of individual and collective experiences shape its meaning. In addition, a Sociology of Security should pay attention to how the kinds of individual and collective responses to particular understandings of security, institutions and policies put in place to this end (or lack thereof), and consequences of such practices are shaping the nature of our social world and the aesthetics of our physical environment. Specific focus is on the relationship between security and surveillance. 相似文献
For a fixed integer k≥0, a k-transmitter is an omnidirectional wireless transmitter with an infinite broadcast range that is able to penetrate up to k “walls”, represented as line segments in the plane. We develop lower and upper bounds for the number of k-transmitters that are necessary and sufficient to cover a given collection of line segments, polygonal chains and polygons. 相似文献
Educational inequalities in health behaviors change dynamically across the life course. Yet, how parental and personal education interactively shape age-specific behavioral inequalities across the transition to adulthood has yet to be understood. Drawing on national Add Health data (N?=?12,605; 6,675 women and 5,930 men), we analyze age- and gender-specific trajectories of current smoking and binge drinking from adolescence to young adulthood. In line with previous work, we find that parental education associates with smoking and drinking disparities even after respondents’ own education is completed. Reciprocally, we also find that disparities by eventual educational attainment appear early. During the college years, higher parental education predicts higher—not lower—rates of binge drinking. We find that attaining higher education “against the odds” of an educationally disadvantaged family background circumscribes the lowest rates of smoking and drinking for men and women alike, and especially during the college years, while “falling from grace” by not attaining higher education at levels matching one’s parents predicts the highest levels of smoking and drinking for both genders during or after college. These results shed new light on the interactive socioeconomic processes that help to explain behavioral health gradients across adolescence and adulthood.