External and Internal Validity of a Geographic Quasi-Experiment Embedded in a Cluster-Randomized Experiment

54 Pages Posted: 22 Jul 2016 Last revised: 2 Sep 2016

See all articles by Sebastian Galiani

Sebastian Galiani

University of Maryland - Department of Economics

Patrick J. McEwan

Wellesley College, Department of Economics

Brian Quistorff

Office of the Chief Economist

Multiple version iconThere are 2 versions of this paper

Date Written: July 21, 2016

Abstract

This paper analyzes a geographic quasi-experiment embedded in a cluster-randomized experiment in Honduras. In the experiment, average treatment effects on school enrollment and child labor were large — especially in the poorest blocks — and could be generalized to a policy-relevant population given the original sample selection criteria. In contrast, the geographic quasi-experiment yielded point estimates that, for two of three dependent variables, were attenuated. A judicious policy analyst without access to the experimental results might have provided misleading advice based on the magnitude of point estimates. We assessed two main explanations for the difference in point estimates, related to external and internal validity.

Keywords: Geographic Quasi-Experiment, RCT, Internal Validity and External Validity

JEL Classification: C18, C93, O22

Suggested Citation

Galiani, Sebastian and McEwan, Patrick J. and Quistorff, Brian, External and Internal Validity of a Geographic Quasi-Experiment Embedded in a Cluster-Randomized Experiment (July 21, 2016). Available at SSRN: https://ssrn.com/abstract=2812690 or http://dx.doi.org/10.2139/ssrn.2812690

Sebastian Galiani (Contact Author)

University of Maryland - Department of Economics ( email )

College Park, MD 20742
United States

Patrick J. McEwan

Wellesley College, Department of Economics ( email )

106 Central Street
Wellesley, MA 02481
United States

HOME PAGE: http://www.patrickmcewan.net

Brian Quistorff

Office of the Chief Economist ( email )

1441 L Street NW
Washington, DC 20910
United States

Do you have a job opening that you would like to promote on SSRN?

Paper statistics

Downloads
61
Abstract Views
882
Rank
472,156
PlumX Metrics