Randomized controlled trials informing public policy: Lessons from project STAR and class size reduction

Moshe Justman

European Journal of Political Economy, 2018, vol. 54, issue C, 167-174

Abstract: Randomized controlled trials (RCTs) and related research strategies are increasingly seen as the preferred methodology for evaluating policy interventions, but a single-minded focus on identifying causal effects limits their capacity to support actual policy decisions. A detailed look at Project STAR illustrates this point and offers some possible correctives. Initiated by the Tennessee legislature to help decide whether to enact state-wide class size reduction (CSR), STAR compared the test scores of students randomly assigned to classes of different size. It addressed a well-formed research question, but focused narrowly on refining a single link in a long chain of evidence necessary to address the policy question at hand: whether CSR would be a good use of a large increase in education spending. It disregarded the limitations of test scores as indicators of education quality and ignored general equilibrium effects on teacher quality and salaries. Moreover, the emphasis it placed on estimating average CSR effects in a given setting diverted attention from the heterogeneity of these effects and the conditions that mediated their impact, limiting its external validity. These observations continue to be relevant for the design of policy-oriented research, and for the academic training of empirical economists.

Keywords: Class size; Project STAR; Randomized controlled trials; Field experiments; Validity; Modern experimentalist paradigm (search for similar items in EconPapers)
JEL-codes: C54 I28 (search for similar items in EconPapers)
Date: 2018
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0176268017305293
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:poleco:v:54:y:2018:i:c:p:167-174

DOI: 10.1016/j.ejpoleco.2018.04.005

Access Statistics for this article

European Journal of Political Economy is currently edited by J. De Haan, A. L. Hillman and H. W. Ursprung

More articles in European Journal of Political Economy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().