Data SGP is a useful resource for educators to help both students and parents better understand the progress their child is making in his or her learning. The tool compares assessment scores of individual students against similar academically-similar students to reveal insights into his or her relative performance relative to his peers – information which allows educators to formulate plans to enhance a student’s performance.
Data SGP should not be the sole factor when making educational decisions; students should be assessed on various metrics, including standardized tests and classroom performance evaluation. Furthermore, educators must consider individual student SGPs when making decisions about how best to support or challenge students as well as using SGP data in curriculum planning processes for future instruction and curriculum planning processes.
SGPs require access to longitudinal (time dependent) student assessment data. Usually this type of information is stored in WIDE format with each case/row representing one student and columns representing variables associated with them at different points in time. The SGP package offers both wide (sgpData_LONG and wide sgpData) and long format data sets (sgpData and sgpData_INSTRUCTOR_NUMBER) which can be used with SGP analyses; they include variables like VALID_CASE, CONTENT_AREA YEAR ID SCALE_SCORE GRADE SCALE_SCORE and GRADE while sgpData_INSTRUCTOR_NUMBER is an anonymized lookup table which associates a teacher to every test record in its long version).
Student growth percentiles are calculated through comparing a student’s score on an exam section with that of other students with similar academic histories, then weighting these comparisons accordingly to derive an individual student rank within his/her cohort from 1-99; with higher numbers signifying improvement.
However, student growth percentiles can be misleading for students who already possess superior academic abilities. A low score in one test section could indicate either difficulty with the subject matter or an absence of effort on behalf of the individual student.
SGPs may be susceptible to spurious correlations arising from differences in school/teacher characteristics or baseline cohort design. Therefore, it is recommended that educators review their SGPs with the assistance of an experienced specialist.
In order to use the SGP package, users must install R on their computer – an open-source programming language available free-of-charge for Windows, Mac OSX or Linux users alike. As SGP analysis uses advanced R functions that require familiarity from its users – numerous resources on CRAN website provide help on getting started with R. For those just getting started with R, additional guidance may be found by consulting the SGP Data Analysis Vignette.