IPR - Institute for Policy Research - Northwestern University

Q
uantitative Methods
for Policy Research
Most researchers and academics tend to stick with the research methods they know best, learned
mainly in graduate school—even though those methods might not represent current best practices or
the most appropriate method. This is why statistician and education researcher Larry Hedges, with
the support of a group of distinguished interdisciplinary scholars, launched the Center for Improving
Methods for Quantitative Policy Research, or Q-Center, at the Institute for Policy Research. Hedges
co-directs the center with social psychologist Thomas D. Cook. Q-Center faculty work on:
• improving designs, analysis, and synthesis in policy research
• designing better research methods for education
• fostering a community of scholars
• developing new data sources and methods of data collection
Overview of Activities
< Partial Knowledge and Identification
Charles F. Manski, Board of Trustees Professor
in Economics, continues his original work on the
difficulties of selecting the best policy with limited
knowledge of policy impacts, which he expounded in
two books, most recently in Identification for Prediction
and Decision (Harvard University Press, 2007).
< Response Errors in Survey Research
Manski and Francesca Molinari of Cornell University
are also working on nonresponse and response errors in
survey research. They hope to improve the researchers’
ability to use data from the Health and Retirement
Study (HRS) by recognizing that some respondent
records are incomplete and possibly error-ridden and
then extend their findings to general survey research.
The two researchers are analyzing HRS data to see
whether they can improve assessment of data quality.
In particular, they want to learn whether certain types
of respondents in large-scale surveys such as the HRS
systematically tend to provide inaccurate or incomplete
information. Most recently, they addressed the use of
skip sequencing, in which respondents are only asked
a certain question or series of questions based on their
response to a broad, opening question. Manski and
Molinari consider various predictions of nonresponse
and response errors, outlining the situations in which
skip sequencing works best. They published their
findings in the Annals of Applied Statistics.
Co-Chairs
Thomas D. Cook (l.), Psychology, and Larry
Hedges, Statistics/Education and Social Policy
Q-Center faculty conduct research relevant to the
center’s mission of improving designs, data collection,
analysis, and synthesis in social policy research.
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