Many school districts in the United States now use "value-added" models to measure teacher effectiveness. These value-added scores are derived from their students' end-of-year test scores, using complex statistical models to adjust for their prior test scores and other factors. In his Brown Bag lecture, Stanford University professor Edward Haertel will address the reliability and validity of teacher value-added scores, asking the same kinds of questions that are routinely asked about other, simpler kinds of test scores. Haertel notes, "Like all measurements, these scores are imperfect. They are appropriate and useful for some purposes, but not for others. Viewed from a measurement perspective, value-added scores have limitations that make them unsuitable for high-stakes personnel decisions."
Edward Haertel is the Jacks Family Professor of Education, Emeritus, at Stanford University. He is an expert in educational testing and assessment and has been closely involved in the creation and maintenance of California's school accountability system. In addition to technical issues in designing accountability systems and quantifying their precision, Haertel is concerned with validity arguments for high-stakes testing, the logic and implementation of standard-setting methods, and comparisons of trends on different tests and in different reporting metrics. SEE FULL BIO>>