Data SGP is a software package that calculates student growth percentiles and projections/trajectories from large scale, longitudinal education assessment data. The results are used to identify students who may require extra support, evaluate current educational systems and to help plan for the future.
The data sgp package can be used to analyze data from multiple sources including standardized tests, portfolios or grading scales. It is also useful for assessing the quality of test administration and identifying ways to improve testing processes. The data sgp package can also be used to evaluate the relationship between teacher qualities and student performance.
The first step in using the SGP package is to convert your data into the proper format. There are two basic formats: WIDE and LONG. The lower level functions, studentGrowthPercentiles and studentGrowthProjections, can work with either format but the higher level wrapper functions, particularly if you plan on running your analyses operationally year after year, are designed to work with LONG data.
Once your data is in the right format it is time to begin running SGP calculations. SGP analyses are generally simple and straightforward. Most errors that occur during the analyses revert back to issues in data preparation so we recommend that you take the time to do your data preparation correctly.
A typical analysis involves two steps: generating the SGP percentiles and generating SGP projections/trajectories. The SGP percentiles are computed by comparing a student’s current MCAS score to the scores of other students who have similar performance histories. The projections/trajectories are then used to determine a projected course of MCAS completion for the student based on their current MCAS progress and their predicted grade point average (GPA).
Depending on the context, you may need to include additional information in your SGP calculations. For example, you may need to know the student’s grade level or gender or if they are an English Language Learner. The SGP package includes a variety of student-instructor lookup tables which can be used to provide this type of information in your SGP calculations.
In the final step, you will need to create a plot of the projections/trajectories and/or SGP percentiles. The SGP package provides a number of plotting functions that can be used to do this.
If you want to get started with SGP analyses, the best way is to download the SGPdata package and exemplar WIDE and LONG formatted data sets from our website. Then, follow the detailed instructions in the SGPdata help file and you will be on your way to analyzing your own data. Good luck! And if you run into any trouble, don’t hesitate to reach out for assistance. We are always happy to help!