International Initiative for Impact Evaluation (3ie)

International Initiative for Impact Evaluation (3ie) promotes evidence-informed equitable, inclusive and sustainable development. 3ie supports the generation and effective use of high-quality evidence to inform decision-making and improve the lives of people living in poverty in low- and middle-income countries. 3ie provides guidance and support to produce, synthesize and quality assure evidence of what works, for whom, how, why, and at what cost.

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Picture-Based Crop Insurance (PBI)

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Publications

Working Paper

Tracing the economic impacts of the 2025 US tariff increases and evaluating possible responses: An analysis for Papua New Guinea

2026Pal, Barun Deb; Andam, Kwaw S.; Pepae, Sanja

Details

Tracing the economic impacts of the 2025 US tariff increases and evaluating possible responses: An analysis for Papua New Guinea

Restrictions on global trade can contribute to adverse economic outcomes in developing countries. Perverse outcomes include reduced export opportunities and higher input costs for essential goods. Policymakers in Papua New Guinea (PNG), as in other developing countries across the world, have therefore been concerned about global trade uncertainty as geopolitical tensions and protectionist policies have escalated throughout 2025. In April 2025, the United States (US) implemented a new tariff policy that included a baseline 10% tariff on goods from all countries, including PNG, along with higher “reciprocal tariffs” on countries with large trade deficits. The PNG government confirmed it would not retaliate but would instead pivot trade toward Asia-Pacific partners such as China, Indonesia, and Japan. In July 2025 PNG’s exports to the US were subjected to a 15% reciprocal tariff under an updated U.S. tariff schedule. In the ensuing months, some countries managed to finalize bilateral trade deals with US and reduced the tariff rates, while others are still under negotiations. According to the US trade policy 2025, the increment in reciprocal tariff on PNG is a result of the country’s failure to take sufficient steps to align with the US (The White House, 2025). In this note, we provide a rapid assessment of the potential impacts of US tariff hikes on PNG’s economy, specifically on trade, GDP, and household income. We consider the two following scenarios: Scenario 1—only US imposes additional tariffs (10 percent, 15 percent, and 30 percent), and PNG does not reciprocate. Scenario 2—PNG reciprocates with equivalent tariffs on the commodity import from the US. This note provides a rapid assessment of impact of US tariff policy on key macroeconomic indicators of PNG. This also helps derive quick policy insights into whether it would be advantageous for PNG to respond with higher tariffs or to accept the US’s higher tariff. Though US has imposed a 15% tariff on PNG’s export to US, due to uncertainty regarding the level of protectionism among the countries, this analysis also considers multiple tariff rates to understand the extent of economic losses in PNG due to relatively higher US tariff in the future.

Year published

2026

Authors

Pal, Barun Deb; Andam, Kwaw S.; Pepae, Sanja

Citation

Pal, Barun Deb; Andam, Kwaw S.; and Pepae, Sanja. 2026. Tracing the economic impacts of the 2025 US tariff increases and evaluating possible responses: An analysis for Papua New Guinea. Papua New Guinea Food Policy Strengthening Working Paper 10. Washington, DC: International Food Policy Research Institute. https://hdl.handle.net/10568/180800

Country/Region

Papua New Guinea

Keywords

Melanesia; Oceania; Capacity Building; Economic Impact; Tariffs; Trade Barriers; Policies; Trade; Computable General Equilibrium Models

Language

English

Access/Licence

Open Access

Source

Source record

Record type

Working Paper

Out-of-sample validation of the external and internal Migration Propensity Index (MPI) in Honduras

2025Ceballos, Francisco; Hernandez, Manuel A.

Details

Out-of-sample validation of the external and internal Migration Propensity Index (MPI) in Honduras

The external and internal Migration Propensity Indices (e-MPI and i-MPI) are tools to objectively estimate the probability that individuals from a given household will, respectively, migrate abroad or migrate domestically in the near future. We use new longitudinal data to test their predictive performance fully out of sample. We find that households classified as being of high-propensity to migrate by the e-MPI were significantly more likely to migrate abroad within 24 months (10.7%) than medium- and low-propensity groups (8.8% and 5.3%). For domestic migration, the i-MPI shows an even stronger gradient (19.6% versus 8.5% and 3.5%, respectively). Regression models confirm that both indices outperform alternative predictors—including income, climate shocks, crime, and migration intent—and maintain predictive power across rural and urban areas. Placebo tests indicate that the e-MPI and i-MPI capture distinct dimensions of migration behavior, validating their use for targeting and monitoring migration-related interventions. Overall, the MPIs emerge as simple yet statistically robust tools that reliably predict both international and domestic migration, offering a practical and scalable solution to help governments and development agencies anticipate migration trends and allocate resources strategically.

Year published

2025

Authors

Ceballos, Francisco; Hernandez, Manuel A.

Citation

Ceballos, Francisco; Hernandez, Manuel A. 2025. Out-of-sample validation of the external and internal Migration Propensity Index (MPI) in Honduras. IFPRI Working Paper. Washington, DC: International Food Policy Research Institute. https://hdl.handle.net/10568/178954

Country/Region

Honduras

Keywords

Central America; Migration; Indicators; Forecasting; Population Dynamics

Language

English

Access/Licence

Open Access

Source

Source record

Project

Fragility, Conflict, and Migration

Record type

Working Paper

The impact of genetically modified cowpea on yields, postharvest losses, and profitability in Nigeria: Findings from a cluster randomized controlled trial

2025Amare, Mulubrhan; Andam, Kwaw S.; Spielman, David J.; Bamiwuye, Temilolu; Zambrano, Patricia; Chambers, Judith A.; Fasoranti, Adetunji; Popoola, Olufemi

Details

The impact of genetically modified cowpea on yields, postharvest losses, and profitability in Nigeria: Findings from a cluster randomized controlled trial

We assess the impacts of a genetically modified pod borer-resistant (PBR) cowpea variety in Nigeria through a cluster randomized controlled trial conducted in two major cowpea-cultivating states. Our design allows us to examine the impacts of PBR cowpea with and without a package of complementary inputs (fertilizer and insecticides) and in comparison to farmers who received only a conventional improved cowpea variety. Results indicate that farmers who received and planted PBR cowpea experienced significant increases in yield (21 percent) and net margins (49 percent) compared to those growing the conventional variety, with larger gains observed among those provided with the inputs package. Analysis of heterogeneous effects indicates substantial variation in outcomes based on baseline characteristics such as household size, landholding, pest control practices, and wealth. Estimation of group average treatment effects and classification analysis using a causal machine learning approach identify plot size, pesticide use, and assets as key drivers of impact heterogeneity. Findings highlight the need for targeted dissemination strategies to realize the sizable benefits of PBR cowpea for small-scale, resource-constrained farmers.

Year published

2025

Authors

Amare, Mulubrhan; Andam, Kwaw S.; Spielman, David J.; Bamiwuye, Temilolu; Zambrano, Patricia; Chambers, Judith A.; Fasoranti, Adetunji; Popoola, Olufemi

Citation

Amare, Mulubrhan; Andam, Kwaw S.; Spielman, David J.; Bamiwuye, Temilolu; Zambrano, Patricia; et al. 2025. The impact of genetically modified cowpea on yields, postharvest losses, and profitability in Nigeria: Findings from a cluster randomized controlled trial. IFPRI Discussion Paper 2383. Washington, DC: International Food Policy Research Institute. https://hdl.handle.net/10568/178553

Country/Region

Nigeria

Keywords

Africa; Sub-saharan Africa; Western Africa; Impact; Genetically Modified Organisms; Seed Damaging Insects; Pest Resistance; Cowpeas; Randomized Controlled Trials; Machine Learning; Smallholders; Information Dissemination; Yields; Postharvest Losses; Profitability

Language

English

Access/Licence

Open Access

Source

Source record

Project

National Policies and Strategies

Record type

Working Paper