Mary E. Laski

13 Appian Way
Harvard University
Cambridge, MA 02138

E-Mail: EmailAddress: hidden: you can email any NBER-related person as first underscore last at nber dot org
Institutional Affiliation: Harvard University

NBER Working Papers and Publications

August 2020Have Income-Based Achievement Gaps Widened or Narrowed?
with Shirin A. Hashim, Thomas J. Kane, Thomas Kelley-Kemple, Douglas O. Staiger: w27714
Since 1990, U.S. policymakers have worked to close gaps in academic achievement by income and race (e.g. with school finance reform and school accountability systems) even as rising income inequality and income-based residential segregation have threatened to widen them. Using estimates of the mean and variance in household income for sampled schools, we reconstruct the student-level relationship between achievement and household income in the National Assessment of Educational Progress (NAEP) from 1990 to 2015. We find that achievement at all levels of parental income rose substantially in 4th and 8th grade. In contrast to Reardon (2011), we find that achievement gaps narrowed substantially in 4th grade reading and math and in 8th grade math, while the gaps remained stable in 8th grad...
February 2016Learning Job Skills from Colleagues at Work: Evidence from a Field Experiment Using Teacher Performance Data
with John P. Papay, Eric S. Taylor, John H. Tyler: w21986
We study on-the-job learning among classroom teachers, especially learning skills from coworkers. Using data from a new field experiment, we document meaningful improvements in teacher job performance when high- and low-performing teachers working at the same school are paired and asked to work together on improving the low-performer’s skills. In particular, pairs are asked to focus on specific skills identified in the low-performer’s prior performance evaluations. In the classrooms of low-performing teachers treated by the intervention, students scored 0.12 standard deviations higher than students in control classrooms. These improvements in teacher performance persisted, and perhaps grew, in the year after treatment. Empirical tests suggest the improvements are likely the result of low-p...

Published: John P. Papay & Eric S. Taylor & John H. Tyler & Mary E. Laski, 2020. "Learning Job Skills from Colleagues at Work: Evidence from a Field Experiment Using Teacher Performance Data," American Economic Journal: Economic Policy, vol 12(1), pages 359-388.

NBER Videos

National Bureau of Economic Research, 1050 Massachusetts Ave., Cambridge, MA 02138; 617-868-3900; email:

Contact Us