Data SGP Explained
Data sgp leverages longitudinal student assessment data to generate statistical growth percentiles (SGPs), which measure students’ relative progress against their academic peers. They are comparable to percentile rank as they indicate whether students have outgrown more than or equal to 75% of their academic peers; although not as extensive as other big data problems, SGP calculations still contain substantial amounts of information that must be accounted for in calculations.
SGPs for each student are calculated based on the latest available data and standardized for comparison across grade spans and tested subjects. The SGP metric helps educators assess whether their students are progressing as expected relative to peers, or if their learning rate falls short of expectation. This allows educators to see whether progress has slowed as expected over time or whether learning rates exceed expectations.
SGPs are calculated based on student performance in each grade level, and aggregated to reveal subgroup and class progress across schools or districts. Median SGPs were often used in this analysis, however the Department believes using mean SGPs more closely aligns with its guiding philosophy that all students contribute towards accountability results.
Student growth percentiles (SGPs) are calculated based on student performance on any assessment. For instance, SGP scores for the 2017 MCAS 4th Grade math exam can be determined by comparing this year’s test score with similar students who performed similarly on prior MCAS tests; typically the more years of data available the more accurate an SGP model will be.
SGPs also serve a useful purpose in teacher evaluation systems, where they are combined with other factors to create an overall evaluation score for every educator. The statewide education evaluation system now features an mSGP for every qualifying principal, assistant principal or vice principal (AP/VP), which contributes a percentage towards their rating overall.
SGPs are essential in understanding student progress; however, interpretation remains complex. To assist educators with understanding these metrics, the Department has created several SGP vignettes. We also created an easy-to-use spreadsheet called sgpData with tools for exploring and analyzing SGP data; educators can download this tool from our BAA Secure Site and explore it as they gain more knowledge of SGPs. Finally, we have also posted an informative video which covers an introduction to SGPs as well as their potential impacts on educators.