The ability to quickly and accurately access information is critically important in any business. This is particularly true when analyzing data. To that end, having a comprehensive and easy to use SGP data set is essential.
The data sgp package includes exemplar WIDE and LONG formatted longitudinal (time dependent) student assessment data sets. These data sets can be used to run the lower level functions (studentGrowthPercentiles and studentGrowthProjections) or the higher level wrapper functions sgpSGPMethods and sgpSGPAnalysis. In most cases it is recommended that the LONG data format be used since this provides numerous preparation and storage benefits over WIDE data sets.
Student growth percentiles measure a student’s progress on MCAS by comparing their current score to the scores of students with similar MCAS performance histories. A student’s growth percentile will range from 1 to 99, with higher numbers indicating greater relative progress and lower numbers indicating less relative progress. For example, a student who has a growth percentile of 75 would have scored better on the MCAS than half of all students with comparable score histories.
In order to calculate growth percentiles, the BAA Secure Site uses data from the most recent year of testing for each student (4th – 11th grades) and compares that student’s score to the performance of students who took the same grade-level test at a previous time point. For example, in ELA, students are compared to their prior year’s test results and in mathematics, the most recent data is used. Since the Badger Exam was administered only in 2014-15, DPI did not report SGPs for grade 9 or science.
Once growth percentiles have been calculated, they can be translated into achievement standards based upon official state achievement targets/goals. This process is illustrated below and can be repeated each year as new achievement targets are established and as the results of those new achievement targets are reported. This will then result in a new per/year growth standard that can be utilized in future educator evaluations. In addition, the same process can also be used to establish per/year growth trajectories which are then used to project future MCAS growth rates for a student. This is a unique feature of the SGP methodology. The resulting per/year growth rate can then be compared to a student’s actual MCAS progress to determine whether or not they are on track to meet the target by the end of the next evaluation cycle. This will help identify any areas of concern for the educator. If not, the teacher may be advised to implement interventions or additional supports. This will hopefully prevent a negative impact on the student’s growth trajectory. It is a best practice to consult with district leadership to determine this process and timing for each school/district. For more detailed information on the SGP methodology, refer to the SGP Methodology page. This page contains several resources and links to helpful documents.