How to Use the Data SGP Tool to Conduct Student Growth Percentile (SGP) Analyses
Data sgp is an online repository of statewide student assessment data that provides educators and other stakeholders with the ability to view the varying degrees of growth of their students. This information can be used to inform instructional decisions. The website is available to all registered users and allows the downloading of individual student cases as well as aggregated data sets. It also provides an opportunity for educators to use the data in ongoing reflections of their teaching practices. The site is maintained by a collaboration of DESE staff and partners.
This article describes how to use the data sgp tool to conduct student growth percentile (SGP) analyses with longitudinal data sets from previous MCAS administrations. It explains how to use the lower level functions studentGrowthPercentiles and studentGrowthProjections as well as the wrapper function prepareSGP, which combines these analyses into a single function call and simplifies the source code associated with running these analyses.
There are two common formats for longitudinal student assessment data: WIDE and LONG format. In WIDE format, each case/row represents a unique student and columns represent variables associated with that student at different times. In the LONG format, time dependent data for a student is spread out over many rows of the spreadsheet.
Each year, the State Education Agency (SEA) produces a report card for each student in Massachusetts. This report card contains a variety of statistical information about the student’s academic performance, including the Student Growth Percentile (SGP) for each subject area tested on MCAS. In addition, the report card also includes information about a student’s attendance and course enrollment.
The SGP calculation is based on trends in statewide student testing results. This means that, over time, a student’s SGP may move up or down depending on a number of factors such as the overall state trend, the rate of change in student achievement during a given year, and how the test-taker’s performance compares to the average performance of his/her academic peers.
For example, Students A and B scored the same on this year’s MCAS test in a content area; however, they had different SGPs because they had significantly different rates of growth with respect to their academic peers.
The sgpData_INSTRUCTOR_NUMBER file is an anonymized student-instructor lookup table that links each student to his/her instructor for the assessment windows in which he/she was tested. This is a required variable if you are using the studentGrowthPercentiles and/or studentGrowthProjections functions to analyze the longitudinal data set. Please note that teachers can have more than one student associated with them, and therefore, a teacher will appear in this table multiple times for each test window. This is a normal part of the SGP analysis process and does not affect the validity or reliability of the SGP calculations. For more information on SGPs, please refer to the MCAS Growth Web page. It provides a description of how to access and interpret SGP reports for administrators, educators, and families.