Using longitudinal student assessment data to generate statistical growth plots (SGPs) that measure students’ relative progress compared to academic peers is an excellent way to identify areas of strength and weakness. Unfortunately, the calculations involved in creating SGPs from standardized test score histories are complex and yield large estimation errors. The SGPdata package makes this work easier and more reproducible. The classes, functions and 4 examplar datasets in the package provide a framework for developing SGP analyses.
In this article, we’ll walk through the creation of a basic SGP analysis using the SGPdata package. Then we’ll discuss the results from this analysis. Finally, we’ll look at some of the potential uses of this powerful tool.
SGPs are plots of a student’s achievement based on their percentile ranking of all other students with similar standardized test scores and covariates. These plots are useful because they allow us to see a student’s progress in a very clear and concise manner. For example, if a student’s SGP shows that they have reached the 75th percentile of their academic peers, we know that they have made above average progress over time.
The SGPdata package provides the tools necessary to analyze and visualize student growth. The package also contains a number of vignettes to help users learn how to use the packages functions and datasets. The SGPdata vignettes cover both the student growth percentile and the teacher level growth projections/trajectories analyses.
The first step in creating a student growth percentile (SGP) is to determine the student’s current achievement level. To do this, we must first find the student’s current standardized test score and the number of attempts that they have taken. Once we have this information, we can calculate the student’s stanine score by dividing the difference between the student’s current standardized test score – the measurement standard – and their previous standardized test score by the number of attempts. We then divide the stanine score by the measurement standard and calculate the percentage of growth that was required to reach the measurement standard. The SGP is then based on this percentage of growth. If the student’s SGP is above the 85th percentile, this means that they have exceeded the growth target. Similarly, if the student’s SGP is below the 85th percentile, this means that the student has not yet achieved the desired level of growth. The SGP is then plotted on a graph and can be used to inform future decisions about the student’s educational program. The SGP can be a useful tool for both teachers and students in making educational decisions. It can also be used to identify areas where additional instructional support is needed. The student growth percentile can be an effective tool for communicating a student’s progress to parents and other stakeholders. It can help ensure that all learners are receiving a quality education. The SGP is one of many components in a well-rounded curriculum. The SGP should be evaluated regularly to make sure that it is addressing the needs of all learners.