Data sgp is a term used to describe the process of conducting student growth projection (SGP) analyses. SGP analyses involve the use of data from multiple student assessments to determine a single student’s growth trajectory over time.
SGP analyses can be conducted in several ways. Typically, they are conducted simultaneously. In some cases, however, one may prefer to use higher level functions (wrapper functions) for these lower level functions.
Often, these wrapper functions provide a “wrap” function call that simplifies the source code for conducting an SGP analysis. This can be especially helpful in operational SGP analyses where it is important to have a clear understanding of the source code.
A good starting point for learning about SGP analyses is to review the documentation of a few different examples. These include the SGP_LONG and sgpData_LONG examples shown below, which illustrate how the WIDE and LONG data formats are represented in the SGP Package.
The WIDE and LONG data formats are common for representing longitudinal (time dependent) student assessment data. In the WIDE format, each case/row represents a unique student and columns represent variables associated with the student at various times.
In the LONG format, the data are distributed across multiple rows in the data set. This allows the analysis to more easily identify a specific student’s growth trajectory over time.
If a student’s assessment data are in the WIDE format, they can be converted to the LONG format by using the sgpData_LONG function. In the LONG format, student growth indices are calculated by multiplying the time-dependent data with a weighted average of all possible student responses to a question.
Some students’ assessment data may be in a combination of the two formats. In these situations, the sgpData_LONG and sgpData_WIDE functions can be combined to allow one to perform an SGP analysis that will incorporate all of the data for each student.
Another common way to conduct SGP analyses is to use the studentGrowthPercentiles and studentGrowthProjections functions. These functions use the sgpData_LONG, sgpData_WIDE, and sgpData_INSTRUCTOR lookup files as inputs.
These files can be created by opening the sgpData_LONG file and then selecting “create” from the menu. These files can also be opened by creating a new project in the SGP Package and importing them.
Alternatively, the data can be imported from a different source and then the WIDE and LONG data sets can be combined using the sgpData_LONG or sgpData_WIDE functions. This method is particularly useful if the data set has been imported from a file that does not have a column containing all of the student’s responses.
For this method, you must be able to specify the date range and time period that you wish to calculate growth indices for. You must also be able to specify the type of analysis you are running.
You should also consider whether you want to use a data file from your school district or your university. This may affect the length of the WIDE and LONG formats and can also impact the number of student growth indices that you can calculate.