Data sgp leverages longitudinal student assessment data to produce statistical growth plots (SGP) which measure students’ relative progress compared to academic peers with similar prior test scores. This information can be shared with educators and families in percentile terms that are familiar to them. However, calculating these percentile estimates can be complex, especially when a student’s test score history includes multiple tests from different testing windows or subject areas, and when the student’s initial assessment score may be biased by school or teacher characteristics or the design of the baseline cohort.
The SGP package offers both WIDE and LONG format student assessment data sets and higher level wrapper functions called studentGrowthPercentiles and studentGrowthProjections to simplify the process of setting up and conducting SGP analyses. In general, most errors associated with SGP analyses arise from issues in the preparation of student assessment data.
The sgpdata package, installed when you install the SGP package, provides exemplar WIDE and LONG format student assessment data to assist in the preparation of your own data set for SGP analyses. The data set sgpData, provided in the sgpdata package, contains 5 years of student assessment data, each year representing one grade level. The first column, sgpData_ID, provides a unique student identifier and the remaining columns, GRADE_2013, GRADE_2014, GRADE_2015, GRADE_2016 and GRADE_2017 provide the scaled student assessment scores associated with the student in each of these 5 years.
In addition to allowing the user to select the appropriate SGP metric for an analysis, the sgpdata package also provides a series of summary reports and graphical views that allow the user to understand how well the selected metric performed in each of the 5 years of data. These reports can be filtered and sorted by a variety of criteria, including student identifier, grade level, subject area, metric, etc.
sgpdata also allows the user to download data from the SGP repository that can be used in other applications, including statistical software packages, such as R. This data is available as a tab delimited text file and is updated regularly with new releases of the SGP package.
SGP is a free and open source software package for analyzing longitudinal student assessment data to generate statistical growth plots (SGP). SGP provides a flexible, customizable framework for the estimation and display of student achievement gains. It can be used for a wide variety of educational purposes, including informing instruction, assessing student/teacher performance and supporting educator evaluation systems.
In order to access the SGP repository and use the sgpdata package, users must have a working knowledge of programming and data analysis. The SGP repository includes a number of tutorials and examples that can be helpful in learning the basics of using the sgpdata package. Additionally, the sgpdata package has an extensive online documentation and vignette that provides more detailed instructions on using the sgpdata package. Lastly, the sgpdata package can be run on Linux, Mac OS and Windows. To run the sgpdata package on these platforms, users must have access to the respective operating system’s repository and a working copy of the sgpdata package.