Performance Measures Based on Test Scores – How Well Do They Predict Principals’ Impacts? (In Focus Brief)

Publisher: Cambridge, MA: Mathematica Policy Research
Sep 29, 2016
Authors
Hanley Chiang, Moira McCullough, Stephen Lipscomb, and Brian Gill

Key Findings: 

  • Average achievement and adjusted average achievement—the measures that do not account for students’ past achievement—provide no information for predicting principals’ contributions to student achievement in the following year.
  • School value-added and adjusted school value-added—the measures that account for students’ past achievement—provide, at most, a small amount of information for predicting principals’ contributions in the following year.
  • Averaging measures across multiple recent years does not improve their accuracy for predicting principals’ contributions in the following year.

This focus brief summarizes findings from a study assessing the extent to which four principal performance measures based on student test scores accurately reflect principals’ contributions to student achievement in future years. The study conducted two sets of analyses using Pennsylvania’s statewide data on students and principals from 2007/08 to 2013/14.

First, the study assessed the extent to which ratings from each measure are stable by examining the association between principals’ ratings from earlier and later years. Second, the study examined the relationship between the stable part of each principal’s rating and his or her contributions to student achievement in future years. Based on results from both analyses, the study simulated each measure’s accuracy for predicting principals’ contributions to student achievement in the following year.