Value-added Based Measures of Teacher Effectiveness and their Determinants in the German National Educational Panel Study

该项目旨在分析教师的有效性及其决定因素的基础上，学生层面的成就数据，从德国国家教育小组研究（NEPS）。现有的美国文献通常使用教师固定效应从学生成绩的增值模型，其中估计的教师固定效应作为教师质量的代理操作化的教师有效性。他们量化了教师对学生学习的整体贡献，包括观察到的和未观察到的教师特征的影响。美国的证据表明，这些教师质量指标的差异可以解释学生成绩总体差异的很大一部分。然而，目前尚不清楚其他教育系统是否也存在这种重大影响;迄今为止，德国还没有类似的估计。因此，该项目的第一个关键目标是填补这一空白，利用NEPS数据的纵向结构来估计学生成绩的增值模型，包括教师的固定效应。根据教师质量的估计分布，我们可以量化具有“有效”的教师对学生成绩的影响，通过与教师质量的一个标准差改进相关的学生成绩的平均增长来捕获。一个特别的目标是将我们的估计与美国现有的证据进行比较，以调查德国教师在效率方面是否更同质。尽管估计高质量的教师的重大影响，教师质量的确切特征定义仍然是一个正在进行的研究课题。NEPS的调查信息超过了教师特征的信息通常在大规模的学生-教师数据集。这使得一套新的分析教师质量的决定因素，包括三大类教师的特点：第一，基本的教师特征，如性别，年龄，经验，教师培训;第二，变量描述的态度和教师的行为;第三，独特的国家教育政策数据的过程中，教师的研究和选择进入教师职业。例如，我们可以检验接受典型教师教育的教师是否与后来决定成为教师的“Quereinsteiger”有系统的不同。我们使用两种不同的方法论来解决教师质量的决定因素问题，这两种方法论都研究教师特质和学生内部学习成绩差异之间的关系，以消除未观察到的学生和学校特征的影响。第一种方法是基于教师质量的估计增值措施，利用学生成绩随时间的变化。第二种方法利用两门学科之间学生成绩的差异。由于这两种方法是基于不同的识别假设，我们可以根据单一的数据来源来实现它们，我们也将能够评估教师特质的估计效果在多大程度上取决于所选择的估计方法。

The project aims to analyze the effectiveness of teachers and its determinants based on student-level achievement data from the German National Educational Panel Study (NEPS). The existing US literature typically operationalizes teacher effectiveness using teacher fixed effects from value-added models of student achievement, where the estimated teacher fixed effects serve as a proxy for teacher quality. They quantify the overall teacher contribution to student learning, including the impacts of observed as well as unobserved teacher traits. The US evidence suggests that variation in these measures of teacher quality can explain a substantial part of the overall variation in student achievement. It is yet unclear, though, whether such substantial effects are also present in other education systems; no equivalent estimates for Germany exist so far. A first key goal of the project is therefore to fill this gap by exploiting the longitudinal structure of the NEPS data to estimate value-added models of student achievement that include teacher fixed effects. Based on the estimated distribution of teacher quality, we can quantify the effects of having an “effective” teacher on student achievement, captured by the average increase in student achievement associated with a one standard deviation improvement in teacher quality. A particular goal is to compare our estimates with the available US evidence to investigate whether German teachers are more homogenous in terms of effectiveness.A second key goal of the project is to study the determinants of teacher quality. Despite the estimated substantial impacts of high-quality teachers, the precise characteristics defining teacher quality remain a subject of ongoing research. The NEPS survey information exceeds the information on teacher characteristics typically available in large-scale linked student-teacher datasets. This allows a new set of analyses of the determinants of teacher quality, covering three broad categories of teacher characteristics: first, basic teacher traits such as gender, age, experience, and teacher training; second, variables describing the attitudes and behavior of teachers; and third, unique NEPS data on the course of teacher studies and the selection into the teaching profession. For example, we can test whether teachers who followed typical teacher education differ systematically from “Quereinsteiger” who decided to become teacher at later stages.We address the question of determinants of teacher quality using two distinct methodological approaches that both study the relationship between teacher traits and within-student variation in academic achievement to eliminate the effect of unobserved student and school characteristics. The first approach is based on the estimated value-added measures of teacher quality that utilize variation in student achievement over time. The second approach uses variation in student achievement between two subjects. Since the two methodological approaches are based on different identifying assumptions and we can implement them based on a single source of data, we will also be able to assess to what extent estimated effects of teacher traits depend on the chosen estimation method.