Heterogeneous Impact Disparity
RCTReview
Standard evaluations often measure public works impacts using broad population averages, obscuring major differences in benefit distribution among participants. When programs recruit individuals with viable alternative income sources alongside the deeply unemployed, overall net impacts become severely diluted.
Picture this
Imagine giving free bus passes to two people: one who already owns a car and one who has no transportation at all. The car owner barely uses the bus pass and sees little change in daily life, while the person without a car uses it every day to get a job, experiencing a massive life improvement.
What the evidence says
The upper quartile of participants who benefited most from the program saw short-term earnings increase by 2.2 times the earnings gain experienced by participants in the lowest quartile.
- Who was studied
- Low-income urban and rural youth participating in public works programs in Côte d'Ivoire.
- How
- Randomized controlled trial measuring distribution of short-term income gains across participant impact quartiles.
What to do
Screen applicant baseline employment levels prior to enrollment to select individuals with zero competing labor opportunities.
From the source
"In the Ivory Coast, for example, the quarter of participants who experienced the greatest program impact saw their short-term earnings increase 2.2 times that of participants in the lowest quarter of program impact."
Public works programs and labor market outcomes.pdf