Evidence that teachers' short-term instructional effects persist over time and predict substantial long-run impacts on students' lives provides much of the impetus for a wide range of educational reforms focused on identifying and responding to differences in teachers' value-added to student learning. However, relatively little research has…

Value-added modeling (VAM), one class of statistical models used to estimate individual teacher's or school's contribution to student achievement based on student test score growth between consecutive years, has become increasingly popular in the last decades. Despite the increasing popularity of VAM, many researchers are concerned about the…