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171.
Theories of candidate positioning suggest that candidates will respond dynamically to their electoral environment. Because of the difficulty of obtaining “bridge votes”, most existing approaches for estimating the ideal points of members of Congress generate static ideal points or ideal points that move linearly over time. We propose an approach for dynamic ideal point estimation using Project Vote Smart’s National Political Awareness Test to construct bridge votes. We use our dynamic estimates to measure aggregate change, to measure individual-level change, and to study the institutional and structural factors that explain the changing positions of House candidates and members of Congress. We demonstrate that while the Republican Party has been selecting increasingly extreme candidates, Democratic incumbents have become more extreme while in office. We also find that the congruence between elected members of Congress and their constituents is mostly explained by the selection as opposed to the responsiveness of the candidate. Nonetheless, we find evidence of dynamic responsiveness of incumbents in specific circumstances. We find that competitiveness, midterm elections, and sharing the president’s party affiliation are associated with greater responsiveness. Conversely, retirement is not associated with a change in responsiveness. We find no evidence of responsiveness of challengers. Finally, we find that close elections draw challengers who are more in line with the district’s ideology.  相似文献   
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To what extent are Russian state agencies involved in predatory behavior, and what are the determinants of their activities? Analyzing a novel data-set comprising 312 cases of illegal corporate raiding (reyderstvo) between 1999 and 2010, this article identifies a shift both in the regional and sectoral distribution of raids over time, as well as an increasing participation of state agencies in criminal raiding attacks. Using panel regression analysis to look at the determinants of increasing state involvement, this article shows that election results for the ruling president and his party, as well as the degree to which elections are manipulated throughout Russia's regions, are significantly and positively correlated with the number of raids in a given region, while regions with governors that have stronger local ties are characterized by a smaller number of attacks. A potential interpretation of these findings is that the federal center may tolerate a certain degree of predatory activities by regional elites, as long as these elites are able to deliver a sufficiently high level of electoral support for the center, with the effect being weaker in regions where the governor is interested in the long-term development of the regional economy.  相似文献   
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Despite evidence that neighborhoods confer both risk and resilience for youth development, the existing neighborhood research has a number of methodological limitations including lack of diversity in neighborhoods sampled and neighborhood characteristics assessed. The purpose of this study was to address these methodological limitations of existing research and to examine the relationship of neighborhood structural and social characteristics to family-level social processes and teacher-reported social competence during early adolescence. The study sample of 3,624 fifth graders (51?% girls) was ethnically diverse, including roughly even proportions of non-Hispanic White, non-Hispanic Black, and Hispanic youth. Neighborhood measures included economic disadvantage derived from the U.S. Census, physical and social disorder obtained by direct observation, and social capital from parental reports. Family-level social processes included parent reported family cohesion and youth reported maternal and paternal nurturance. We found that neighborhood factors significantly associated with youth social aggression and social competence but not social withdrawal, after controlling for individual demographic characteristics and parenting factors. There was limited evidence of moderation of family influences by neighborhood characteristics as well as the moderation of neighborhood effects by children’s gender. Neighborhood physical disorder was associated with increased social aggression among boys but with increased social withdrawal among girls. Implications of the study’s findings for research on neighborhoods and adolescent development and the development of preventive interventions are discussed.  相似文献   
176.
School engagement, or the extent to which students are involved in, attached and committed to the academic and social activities in school, plays a prominent role in preventing academic failure, promoting competence, and influencing a wide range of adolescent outcomes. Although the multidimensional nature of school engagement is well-recognized, how the three purported parts of the construct work together is largely unknown. By using data from the longitudinal, 4-H study of Positive Youth Development, involving a sample of 1,029 adolescents (67.7 % female; mean age at Grade 9 = 14.92 years; 74.4 % of participants were European American, 5.2 % were Latino/a, 7.3 % were African American), the current study examined the interrelationships of behavioral, emotional, and cognitive aspects of school engagement over three years in adolescence (Grades 9–11). We used autoregressive lagged effects models to assess the relationships among the three engagement constructs. Results indicated that behavioral and emotional engagement were related bidirectionally (each variable was a basis and an outcome of the other). In addition, behavioral engagement influenced cognitive engagement (but the reverse of this relation was not found). Implications for future research are discussed.  相似文献   
177.
The positive youth development perspective, a strength-based relational developmental systems model that focuses on mutually influential relationships between individuals and contexts, has been used to study thriving across the second decade of life. However, more attention has been paid empirically to identifying the features of the individual (e.g., intentional self regulation, hope, or purpose) or to enumerating the role of context-general ecological assets than to the nature of individual-context relationships linked to thriving within specific contexts. The goal of this special section is to provide initial research reports about context-specific instances of the thriving process. The research focuses on two contexts where many youth spend a considerable amount, and often the majority, of their time—school and out-of-school time sports activities.  相似文献   
178.
Sipping alcohol during childhood may be a marker of differentiation as regards children’s future risk of underage drinking; yet very little is known about alcohol use when it occurs among elementary school-aged children. The purpose of the present study is to examine alcohol sipping behavior in a sample of third-grade school children to learn whether sipping is associated with attributes that could increase children’s likelihood of further underage drinking. We collected telephone interview data from 1,050 mothers and their third grade children (mean age 9.2 years; 48.2 % male) residing in the Southeastern United States. The majority of mothers were White non-Hispanic (69.02 %) or Black non-Hispanic (21.3 %); most (85 %) lived in households shared with fathers or other adult caretakers. We hypothesized that children who sip alcohol would score lower than abstinent peers on indicators of competence and score higher on indicators of exposure to alcohol-specific socialization by parents and peers. A multivariate model controlling for frequency of parent alcohol use and demographic covariates showed that children who had sipped alcohol were significantly less likely than abstinent peers to affirm indicators of competence and significantly more likely to affirm indicators of exposure to alcohol specific socialization by parents and by same age peers. These preliminary findings suggest that developmental attributes associated with risk of underage drinking begin to differentiate at least as young as middle childhood. Research is needed to test prospectively for continuity between alcohol risk attributes present in middle childhood and future alcohol use.  相似文献   
179.
180.
Agroecology has played a key role in helping Cuba survive the crisis caused by the collapse of the socialist bloc in Europe and the tightening of the US trade embargo. Cuban peasants have been able to boost food production without scarce and expensive imported agricultural chemicals by first substituting more ecological inputs for the no longer available imports, and then by making a transition to more agroecologically integrated and diverse farming systems. This was possible not so much because appropriate alternatives were made available, but rather because of the Campesino-a-Campesino (CAC) social process methodology that the National Association of Small Farmers (ANAP) used to build a grassroots agroecology movement. This paper was produced in a ‘self-study’ process spearheaded by ANAP and La Via Campesina, the international agrarian movement of which ANAP is a member. In it we document and analyze the history of the Campesino-to-Campesino Agroecology Movement (MACAC), and the significantly increased contribution of peasants to national food production in Cuba that was brought about, at least in part, due to this movement. Our key findings are (i) the spread of agroecology was rapid and successful largely due to the social process methodology and social movement dynamics, (ii) farming practices evolved over time and contributed to significantly increased relative and absolute production by the peasant sector, and (iii) those practices resulted in additional benefits including resilience to climate change.  相似文献   
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