Data sgp is the process of evaluating student growth using longitudinal education assessment data. It uses a combination of statistical methods to provide a more accurate, precise and meaningful measurement of student achievement. It is a valuable tool for understanding a student’s progress toward proficiency and to identify the potential for future success.
SGP analyses convert raw student scores into scaled scores for comparison with an average of all students in a grade and subject area. They also determine whether a student’s score falls above, below or at an equal level as this average, and then report on the percentage of students in the group that have attained proficiency. SGP programs also compare individual student’s historical growth trajectories with projections from previous years to predict what their scores will be in future years.
The lower level functions that do the calculations (studentGrowthPercentiles and studentGrowthProjections) require WIDE format. They take a set of data points, an SGP target, and an indicator variable such as grade or subject. They then apply a formula to calculate a range of projected scores for the student based on their current and previous performance.
An SGP target is the number of points a student must achieve by a specified date in order to be proficient. For example, a target of 75th percentile means that the student needs to reach a score on the next assessment that is higher than 90% of students with similar MCAS performance histories.
The SGP calculator in the online portal normalizes all scale scores across multiple years and assessments to a common 0-100 score for graphing purposes. This allows districts to see growth graphs for their students on a single page and provides an apples-to-apples comparison of all student results in the district.
In addition, the SGP calculator includes a function to compute student growth percentiles for all of the available indicators in a particular grade. These percentiles are based on the same calculations as the ones used for current SGPs, but without requiring the use of a single test in a given year.
The bulk of time and effort required to conduct SGP analyses is spent in data preparation. This is why the SGP package provides the abcSGP and updateSGP functions to simplify the two step SGP analysis process. These functions “wrap” the 6 steps in the above process into a single function call, and then combine the results of this analysis back into the master longitudinal record, Demonstration_SGP@Data. The final result is a complete and reliable record of all student growth outcomes and projections. This record can be easily retrieved for subsequent annual SGP analyses.
