Data sgp is an application that leverages longitudinal student assessment data to produce statistical growth plots (SGP) which measure students’ relative progress compared to academic peers. The SGP methodology is unique in that it allows for the establishment of an individualized growth standard for each student. This is done by translating an official state achievement goal/target into a growth standard using the student’s prior test score history. A student’s growth percentile is then determined based upon this individualized growth standard. The SGP method can be applied to any number of subjects, grade levels and/or individual students.

To use the data sgp application, one must first have access to a computer with R installed. This is an open source software package available for Windows, OSX and Linux. It is recommended that users spend some time familiarizing themselves with R before attempting to run SGP analyses.

The SGP application is easy to use, although it does require some understanding of statistical concepts and data regresssion. An extensive help file is provided with the application that details many of these concepts and the SGP function is explained in detail.

When a user is ready to begin using the SGP application, they should specify an identifier for each student and a list of subject-matter tests for which growth calculations are desired. Then, the SGP function will be called with the appropriate input parameters. A number of argument are optional and can be used to control the type of SGP produced. For example, a boolean argument can be used to indicate whether the SGP function should convert growth percentiles from 1 to 99 or not. Moreover, a vector of quantiles can be submitted for which the SGP function will perform a quantile regression estimation. Finally, a goodness of fit output is returned to the user.

SGP is an excellent tool for assessing student growth and making curricular decisions. However, as with all measures of student performance there are limitations. For example, SGP results can be biased by a large amount of variation in prior test scores. SGP results should be viewed in conjunction with other sources of information when evaluating the effectiveness of a program or school.

As a result, SGP should be considered as a supplement to traditional measures of student success and not as a replacement. However, it is important to understand the limitations of SGP in order to make informed curricular decisions based on evidence. Despite these limitations, SGP has become an important part of the state accountability system.