Data sgp refers to the collective of aggregated student performance data collected over time and used by teachers and administrators. This data can be used to identify areas for improvement, inform classroom practice, evaluate schools/districts and support broader research initiatives.
SGP analyses convert raw student scores into scaled scores that are then compared with the average of the norm group (typically an entire grade cohort of students in a state across a given content area) to determine whether the student’s score is above, below, or at the same level as that average. It can also predict what the student’s score will be in future years based on the rate at which they have been progressing through the content area over time.
A student’s growth percentile identifies how their current assessment score ranks relative to other students with similar prior test scores (their academic peers). Although the calculations are complex, this information can be shared in terms that are familiar to teachers and parents. It does not tell whether or not a student’s current achievement level is adequate and therefore should not be seen as a replacement for other student performance metrics like value-added models.
For those new to SGP, the bulk of our work in assisting with the implementation of these analyses revolves around ensuring that the right data is being used for these calculations and that it is formatted correctly. Once these two steps are complete, the actual analysis is relatively straightforward and most errors that arise in this process usually revert back to issues in data preparation.
SGP calculations rely on data sets that are stored in the long format and include both the student data and embedded SGPstateData meta-data. The lower level functions that do the actual calculations, like studentGrowthPercentiles and studentGrowthProjections require this type of data set to be able to operate. The higher level functions that are designed to serve as wrappers for these lower level functions, such as summarizeSGP and studentGrowthPlots, also require this long format data set.
The data set sgptData_LONG contains anonymized student assessment records in the long format for a given year with up to five windows (3 windows annually). It includes the following variables: VALID_CASE, CONTENT_AREA, YEAR, ID, SCALE_SCORE and GRADE. It also contains the demographic/student categorization variables, if desired, that are required for all SGP analyses.
The sgptData_LONG is available for download from the NGSS website and is the recommended data set for use with SGP analyses. To access the sgptData_LONG, click on a student in the SGP Summary Report and select “SGP Data” from the “Report Options” menu. Then select the “sgpData” tab, which displays a spreadsheet that shows the student’s SGP scores for each of the 5 windows. The first column, ID, provides a unique identification for each student. The subsequent columns, SS_2013, SS_2014, SS_2015, and SS_2016, provide the student’s assessment scores for each of the five windows. This spreadsheet can be used to generate individual student reports or to create student aggregates for a given window.