In Simple Words
Imagine checking whether a new tutoring program improved class performance. Instead of calculating a single average test score that could be pulled up by one top student, you measure the test scores at the 10th, 50th, and 90th percentiles to prove that students at every level improved.
Eligible young applicants in Cote d Ivoire
- Not assigned a formal apprenticeship
- Group used for comparison
- Assigned subsidized dual apprenticeship
- Total earnings 15% higher
Average total earnings effect. Distribution tests support broader gains but do not prove an equal positive effect at every quantile or for every youth.
See source →Research question
Average treatment effects on labor market earnings can be distorted by extreme high-earning outliers, masking zero or negative impacts for the majority of program beneficiaries.
Participants
N = 1,670 youth respondents surveyed at 4-year endline follow-up in Côte d'Ivoire.
Study Design
Unconditional quantile treatment effect (UQTE) estimation and Mann-Whitney rank-sum permutation tests (10,000 replications) on 4-year total monthly earnings.
Results
The cumulative distribution of total earnings for treated youth shifted uniformly rightward across all quantiles (Mann-Whitney permutation p = 0.0005), confirming medium-term earnings gains (+15%, p = 0.0169) were distributed across low, middle, and high earners rather than driven by outliers.
Takeaway
Estimate unconditional quantile treatment effects and run permutation-based rank-sum tests to confirm program earnings gains are distributed across the entire income distribution.
Source and citation
See source →Read alongside the research
Plain-English glossary
Original explanations, informed by the references below. Examples are illustrations, not data from the studies above. The research text stays unchanged.
- Follow-up
Collecting more information about participants later in a study to see what has happened to them. The term can also mean the length of time researchers keep track of them.
ExampleResearchers interview the same workers three months after a programme ends. That later interview is a follow-up.
GET-IT glossary · Follow-up ↗Read more about follow-up →