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Policy Impact Evaluation Research Initiative (PIERI)

Experimental research

Using experimental approaches to conduct rigorous impact evaluations of social policies/programs on targeted populations in developing countries.

Results from PEP experimental impact evaluation projects provide scientifically-sound empirical evidence to inform program managers, donors, policymakers and civil society on program effectiveness, budget use and ways to improve the design of future interventions.

This evidence that is either meant or can be used to:  

  • Inform decisionmakers, donors and taxpayers on the realization of expected benefits
  • Help improve and assist in program design and implementation
  • Foster accountability of implementation processes
  • Generate political support for continuation or expansion of programs, both within and beyond national boundaries (public good value)

In addition, through the global infrastructure of PEP, the PIERI program also encourages comparative analyses between researchers from around the world, and especially in developing countries of Africa, Asia and Latin America, to compare methods, tools, findings and experience of impact evaluation projects.

Browse through the left-side menu to find the lists of PEP-supported projects, publications and researchers associated with this type of research.


Methods: Randomized Controlled Trials and Field Experiments

Randomized controlled trials (RCTs) use random assignment to allocate the program or intervention being analyzed. They are generally considered the gold standard for policy evaluation, producing unbiased results. To quantify the impact of the intervention, the outcomes of the units receiving the program are compared against those who did not receive it.

Field experiments use controlled environments that make it possible to clearly identify the effect of a treatment and/or learn about micro-motives for behavior.

Glenn Harrison and John List provide a taxonomy of experiments in their article “Field Experiments” in the Journal of Economic Literature (2009). See also, the J-Pal repository of articles from the Handbook of Field Experiments (2017), and the Journal of Economic Behavior and Organization (JEBO) special issue on Field Experiments in Developing Countries. The book, “Field Experiments”, by Alan Gerber and Donald Green is a useful tool for writing proposals.

The PEP-PIERI group encourages researchers to think of creative ways to adapt well-known experimental protocols to answer research questions relevant to local barriers faced by subjects in developing countries.

Both types of projects (RCTs and field experiments) require a good institutional knowledge of the program under study, in terms of:
  • Eligibility rules and the target population
  • Objectives of the intervention and its potential unintended effects
  • Outcomes that may potentially be affected by the program
  • The intervention calendar and the timing of effects (short-term, medium-term, long-term)

NEW! interactive training material:

"Impact Evaluation Using Stata"

    PIERI scientific support team

    The PIERI program and related research/support activities are managed by the following team:

    With support from a group of PEP resource persons, who are leading international experts in the field of microeconomic analysis.




    Funded by