- Using PVAAS for a Purpose
- Key Concepts
- Concept of Growth
- Growth Measures and Standard Errors
- Growth Standard Methodology
- Predictive Methodology
- Topics in Value-Added Modeling
- Public Reports
- Additional Resources
- General Help
This section of the online Help contains information about fundamental concepts in the PVAAS reporting. Having a basic understanding of these concepts will enhance your use of the data in the reports.
How PVAAS Measures Growth
Each year, the academic performance of students is evaluated using a variety of assessments. LEAs/Districts, schools, and teachers receive results from these assessments, which provide important information about the achievement level of their students in tested grades and subjects or Keystone content areas. This information includes the number and percentage of students who performed in each of the state's academic performance ranges—Advanced, Proficient, Basic, and Below Basic. Achievement data from previous years is also included for comparison.
But because the achievement data is based on different groups of students each year, direct comparisons of data across years are often not meaningful or useful. For example, comparing the performance of last year's fifth graders to the performance of this year's fifth graders does not tell us how much academic growth either group of fifth graders made.
We offer a different set of measures. The growth of each group of students is measured as they move from one grade to the next or enter and complete a Keystone course. This approach yields growth measures that are fair, reliable, and useful to educators.
The process begins by generating measures of the average entering achievement level of the group of students served by each teachers, schools, and LEAs/districts. Then a similar measure is generated for the group's average achievement level at the end of the subject and grade or course. To ensure that the measures are precise and reliable, PVAAS incorporates state assessment data across years, grades, and subjects for each student.
The difference between these two achievement measures is calculated and then compared to a standard expectation of growth called the growth standard. Growth color indicators are then assigned to indicate how strong the evidence is that the group of students exceeded, met, or fell short of the growth standard.
Simply put, the expectation is that regardless of their entering achievement level, students should not lose ground academically, relative to their peers in the same grade and subject or course in the reference group. This standard is reasonable and attainable regardless of the entering achievement of the students served.
With this approach, it's possible for a group of students to demonstrate high growth, even if all of them remain in the same state performance level from one year to the next. Each performance level includes a range of scores, so it's possible for a group's average achievement to rise or fall within a single state academic performance level.
There are no individual student measures of growth in PVAAS. This is because there are so fewer data points for an individual student and the error around that measure would be larger, making it difficult to know if a student made growth or not. However, growth measures based on groups of students include much more data, so the impact of measurement error associated with each individual test score is minimized. PVAAS uses many years, grades, and subjects in the analyses. Because so much data is included, the academic growth of the group can be measured with much greater precision and reliability than the growth of a single student. In PVAAS Value-Added reports, a group of 11 students is needed to calculate a measure of growth. In PVAAS Diagnostic reports, a group of five students in any achievement category is needed to calculate a growth measure.