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971.
Youth living in impoverished urban neighborhoods are at risk for becoming hopeless about their future and engaging in violent behaviors. The current study seeks to examine the longitudinal relationship between social connections, hopelessness trajectories, and subsequent violent behavior across adolescence. Our sample included 723 (49% female) African American youth living in impoverished urban neighborhoods who participated in the Mobile Youth Survey from 1998 through 2006. Using general growth mixture modeling, we found two hopelessness trajectory classes for both boys and girls during middle adolescence: a consistently low hopelessness class and an increasingly hopeless class with quadratic change. In all classes, youth who reported stronger early adolescent connections to their mothers were less hopeless at age 13. The probability of later adolescent violence with a weapon was higher for boys and was associated with the increasingly hopeless class for both boys and girls. Implications for new avenues of research and design of hope-based prevention interventions will be discussed.  相似文献   
972.
Many argue that the composition of a school or classroom‐that is, the characteristics of the students themselves‐affect the educational attainment of an individual student. This influence of the students in a classroom is often referred to as a peer effect. There have been few systematic studies that empirically examine the peer effect in the educational process. In this research, we examine the peer effect with a unique data set that includes individual student achievement scores and comprehensive characteristics of the students' families, teachers, other school characteristics, and peers for five countries. The data allow an examination of peer effects in both private and public schools in all countries. Our analysis indicates that peer effects are a significant determinant of educational achievement; the effects of peers appear to be greater for low‐ability students than for high‐ability students. The finding is robust across countries but not robust across school type. © 2000 by the Association for Public Policy Analysis and Management.  相似文献   
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977.
Electoral volatility is much higher in new than in advanced democracies. Some scholars contend that weak partisan ties among the electorate lie behind this high volatility. Political parties in new democracies do not invest in building strong linkages with voters, they claim; hence partisanship is not widespread, nor does it grow over time. Our view is that democratic processes do encourage the spread of partisanship and hence the stabilization of electoral outcomes over time in new democracies. But this dynamic can be masked by countervailing factors and cut short by regime instability. We expect that, all else being equal, volatility will decline over time as a new democracy matures but increase again when democracy is interrupted. We use disaggregated ecological data from Argentina over nearly a century to show that electoral stability grows during democratic periods and erodes during dictatorships.  相似文献   
978.
Although the federal No Child Left Behind program judges the effectiveness of schools based on their students' achievement status, many policy analysts argue that schools should be measured, instead, by their students' achievement growth. Using a 10‐year student‐level panel data set from North Carolina, we examine how school‐specific pressure associated with status and growth approaches to school accountability affect student achievement at different points in the prior‐year achievement distribution. Achievement gains for students below the proficiency cut point emerge in schools failing either type of accountability standard, with the effects clearer for math than for reading. In contrast to prior research highlighting the possibility of educational triage, we find little or no evidence that failing schools in North Carolina ignore the students far below proficiency under either approach. Importantly, we find that the status, but not the growth, approach reduces the reading achievement of higher performing students. Our analysis suggests that the distributional effects of accountability pressure depend not only on the type of pressure for which schools are held accountable (status or growth), but also the tested subject. © 2010 by the Association for Public Policy Analysis and Management.  相似文献   
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980.
Public concerns about the costs of immigration and crime are high, and sometimes overlapping. This article investigates the relationship between immigration into a metropolitan area and that area's crime rate during the 1980s. Using data from the Uniform Crime Reports and the Current Population Surveys, we find, in the cross section, that cities with high crime rates tend to have large numbers of immigrants. However, controlling for the demographic characteristics of the cities, recent immigrants appear to have no effect on crime rates. In explaining changes in a city's crime rate over time, the flow of immigrants again has no effect, whether or not we control for other city-level characteristics. In a secondary analysis of individual data from the National Longitudinal Survey of Youth (NLSY), we find that youth born abroad are statistically significantly less likely than native-born youth to be criminally active.  相似文献   
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