2 resultados para Student t distribution
em Repositório digital da Fundação Getúlio Vargas - FGV
Resumo:
School violence has recently become a central concern among teachers, students, students' parents and policymakers. Violence can induce behaviors on educational agents that go against the goals of improving the quality of education and increasing school attendance. In fact, there is evidence that school environmental characteristics and student performance and behavior at school are related. Although school violence may have a direct impact on students’ performance, such impact has not yet been quantified. In this paper, we investigate this issue using Brazilian data and show that, on average, students who attended more violent schools had worse proficiency on a centralized test carried out by the Brazilian Ministry of Education, even when we controlled for school, class, teachers and student characteristics. We also show that school violence affects more the students from the bottom of the proficiency distribution. Furthermore, we find out that besides the direct effect on student proficiency, it seems that school violence has an indirect effect on it operating through teacher turnover. Indeed, we show that the occurrence of violent episodes in a school decreases the probability of a class in that school having only one teacher during the academic year, and increases the probability of that class having more than one teacher (teacher turnover).
Resumo:
To assess the quality of school education, much of educational research is concerned with comparisons of test scores means or medians. In this paper, we shift this focus and explore test scores data by addressing some often neglected questions. In the case of Brazil, the mean of test scores in Math for students of the fourth grade has declined approximately 0,2 standard deviation in the late 1990s. But what about changes in the distribution of scores? It is unclear whether the decline was caused by deterioration in student performance in upper and/or lower tails of the distribution. To answer this question, we propose the use of the relative distribution method developed by Handcock and Morris (1999). The advantage of this methodology is that it compares two distributions of test scores data through a single distribution and synthesizes all the differences between them. Moreover, it is possible to decompose the total difference between two distributions in a level effect (changes in median) and shape effect (changes in shape of the distribution). We find that the decline of average-test scores is mainly caused by a worsening in the position of all students throughout the distribution of scores and is not only specific to any quantile of distribution.