Data Sgp is a process that is used to help schools analyze current student assessment results and predict how much progress each student is likely to make over time. The goal of this article is to describe how the process works, and what benefits it can provide. The article will also discuss the potential issues that can arise, and how they can be overcome.
In addition to demonstrating the value of the SGP, this paper illustrates how the individual-level relationships between teacher and student characteristics can introduce substantial measurement error into estimated teacher effects (or “SGPs”). This source of variance is easily avoidable in a value-added model that regresses student test scores on teacher fixed effects, prior test score, and student background variables, but it remains present in aggregated estimates of educator effectiveness that rely on direct comparisons of students with similar prior achievement levels.
A primary objective of the SGP process is to generate estimates of individual student growth based on the correlations between standardized test scores and subject-matter tests administered over time. A secondary objective is to generate aggregated estimates of student growth for groups of students, such as classrooms or school districts. In order to facilitate the creation of these aggregated estimates, the SGP process uses student-level regressors that are calculated from the correlations of the same set of individual-level regressors. These regressors are used to estimate the average value added for each student in each classroom or school district, as well as the overall group mean SGP for each cohort of students.
The sgptData_LONG data set contains the same demographic/student categorization variables as the sgpData dataset, but in LONG format, and it also contains 5 additional columns, including DATE, VALID_CASE, CONTENT_AREA, YEAR, ID, and SCALE_SCORE, which are required for use with the SGP function to create student aggregates for various analyses, such as student growth projections. sgptData_LONG is the preferred data set for creating student aggregates for use with SGP analyses.
This figure shows the distribution of the spread of the 0.10 and 0.90 quantiles of the true SGP, as well as the corresponding reliability l for each one. The top half of the figure shows the spread of true SGPs by subject, with math in the first column and ELA in the second. The bottom half of the figure shows the distribution of true SGPs by teacher, with teachers in the upper left of the figure showing a higher mean SGP than those in the lower right, and vice versa. The difference in mean SGPs between the two rows is due to random variation in teacher sorting and contextual effects. In other words, teachers tend to serve different kinds of students. This fact complicates interpreting the true SGPs aggregated to the teacher or school level as indicators of teacher quality. The figure also suggests that aggregated SGPs are not suitable as a replacement for traditional value-added models in most situations. Instead, such models should be used in conjunction with other measures of teacher performance.
