Case Studies: Overview | Dallas | Houston | Plano
In 1992, the Dallas Independent School District (ISD) began implementing value-added analysis – Dallas Value-Added Assessment System (DVAAS) – based on a statistical approach developed within the district. Since then, the district has a rich history of using value-added analysis to assess performance and improve instruction. One of the cornerstones of the Dallas system has been the District’s Accountability Task Force, which is a committee of individuals appointed by the board of education. The task force represents multiple stakeholders – parents, teachers, school administrators, community members – and is responsible for reviewing and approving the selection and weighting of the variables that serve as the foundation of the accountability and performance awards systems.
The statistical elements and uses of DVAAS are discussed in more detail below.
Statistical Elements of the Model
The Dallas value-added model (DVAAS) is categorized as a covariate adjustment model, meaning that it treats a student’s current score as a function of prior scores and other covariates. When measuring students and schools, DVAAS uses a two-stage model which controls for certain “fairness variables” such as
- Preexisting student differences in ethnicity, gender, language proficiency, socioeconomic status, and prior achievement levels.
- School level variables including mobility, percent minority and socioeconomic status.
- Educational variables such as student attendance rates and dropout rates.
Only students with complete test data for the current and prior year are included in the analysis. For more details on the statistical approach, click here.
Uses of the Model
Over the years, Dallas has used value-added analysis to guide a number of different accountability initiatives. Initially, DVAAS focused mainly on identifying effective schools using a “school effectiveness index” composed of scores on various tests and other metrics, such as attendance rates, promotion rates, dropout rates, and enrollment in specific high-level courses. Teachers and principals in the most effective schools identified through this methodology were awarded bonuses. In 1994-1995, the Dallas task force expanded this system and developed a “teacher effectiveness index” which was used to identify teachers in need of extra support.
Most recently, in 2007-2008, Dallas introduced its Pay for Performance Program in 59 schools. The Pay for Performance Model rewards teacher for five key components – (1) serving in high needs’ schools, (2) student performance, (3) academic leadership, (4) professional development, and (5) demonstration of skills. The student performance component (based on value-added analysis) consists of three major categories:
- School-level achievement. The school-level award is determined by the school effectiveness index, which measures the amount of gain students at a school make compared to other schools with a similar student population.
- Classroom-level achievement. Classroom effectiveness indices are used to determine if teachers improve their students’ performance enough to qualify for a performance pay award.
- Subject or grade-level awards. Subject and grade-level awards fall under the Texas Educator Excellence Grant (TEEG) or District’s Awards for Teacher Excellence (D.A.T.E). programs. (http://www.txeducatorawards.org/about.html, Read more about these programs).
This document provides a detailed overview of the five components of the Dallas Performance Pay Initiative.