Now Available: Impact Evaluation in Practice handbook (2nd Edition)

The second edition of the ​I​mpact Evaluation in Practice handbook is now available. The handbook is a comprehensive introduction to impact evaluation for policymakers and development practitioners. The updated version covers the latest techniques for evaluating programs, with expanded case studies.

New Publications

Aspiration Adaptation in Resource-Constrained Environments (Forthcoming in Journal of Urban Economics)
We use a multi-country field experiment that combines random variation at the treatment level with exogenous variation in the length of exposure to treatment to test the effect of a slum-housing intervention on the evolution of housing aspirations of untreated co-resident neighbors. Initially after the intervention, we observe a large housing gap in favor of treated units. As a result, non-treated households’ aspirations to upgrade their dwelling increased sharply relative to the treatment group, echoing an aspiration to “keep-up” with the treated Joneses’. The aspirational effect is mostly observed among dwellers residing in urban slums, with relatively high levels of income, and located close to treatment neighbors. However, after 2 years of treatment exposure, the aspirational effect completely disappears and no effects are found on housing investment. Estimates based on a structural model of aspiration adaptation show that the decay rate is 38% per month, implying that housing aspirations return to baseline levels in just 28 months. Our evidence suggests that simply fostering housing aspirations may be insufficient to encour-age housing investment in poor neighborhoods, and thus slum-upgrading policies designed to indirectly stimulate housing expansion may not be as effective as they promise to be.

How Debit Cards Enable the Poor to Save More Debit Cards Enable the Poor to Save More (Journal of Finance, forthcoming) We study an at-scale natural experiment in which debit cards are given to cash transfer recipients who already have a bank account. We find that beneficiaries accumulate a savings stock equal to 2 percent of annual income after two years with the card. The increase in formal savings represents an increase in overall savings, financed by a reduction in current consumption.  

Living Up to Expectations: How Vocational Education Made Women Better Off But Left Men Behind (Labour Economics 2020) We study an at-scale natural experiment in which debit cards are given to cash transfer recipients who already have a bank account. We find that beneficiaries accumulate a savings stock equal to 2 percent of annual income after two years with the card. The increase in formal savings represents an increase in overall savings, financed by a reduction in current consumption.  

Heat Exposure and Global Air Conditioning  (Nature Sustainability 2019) Air conditioning adoption is increasing dramatically worldwide as incomes rise and average temperatures go up. Using daily temperature data from 14,500 weather stations, we rank 219 countries and 1,692 cities using a widely-used measure of cooling demand called total cooling degree day exposure. India, China, Indonesia, Nigeria, Pakistan, Brazil, Bangladesh, and the Philippines all have more total cooling degree day exposure than the United States, a country which uses 400 terawatt-hours of electricity annually for air conditioning. 

Long-Run Effects of Temporary Incentives on Medical Care Productivity (American Economic Journal: Applied Economics 2019) - This papers uses a randomized field experiment conducted in Argentina​ to show that costs of adjustment as opposed to low perceived value may explain why improved quality care practices diffuse slowly in the medical industry.

​Digital Financial Services Go a Long Way: Transaction Costs and Financial Inclusion (American Economic Association Papers and Proceedings 2019). Debit cards reduce the travel distance to access bank accounts and can increase financial inclusion. We show that in Mexico, cash transfer beneficiaries who already received their transfers in bank accounts and subsequently received debit cards reduce their median distance to access the account from 4.8 to 1.3 kilometers. Using account level data, we find a strong correlation between the reduction in travel distance and both their number of withdrawals and their savings balances.

New Working Papers

Another Brick in the Wall: The Effect of Non-contributory Pensions on the Material and Psychological Well-Being of Older Adults (2021)  Public expenditures on non-contributory pensions are equivalent to at least 1 percent of GDP in many countries in Latin America and is expected to increase. We explore the effect of non-contributory pensions on the well-being of the beneficiary population with data from a field experiment of the Pensiones Alimentarias program in Paraguay, which targets older adults living in poverty. Households with a beneficiary increased their level of consumption by 44 percent and older adults increased their leisure by reducing labor supply. The program also improved a psychological well-being index by 0.48 standard deviations. The well-being index is composed of a depression symptom scale (which itself decreased 7 percentage points), reported satisfaction with quality of life, empowerment, feeling of contribution to the expenditures common to all household members, and perception of self-worth. Beneficiaries also reported suffering less illnesses (a decrease of 6 percentage points) and perceived better health (an of 8 percentage points for good or very good health). This study is to our knowledge the first to provide experimental evidence on the impact of non-contributory mechanism on well-being. The results are consistent with the findings of observational studies; Bando, Galiani and Gertler (2020) in Peru and Galiani, and Gertler and Bando (2016) in Mexico. Thus, the effects of non-contributory pensions on well-being in Paraguay are comparable to those found for Peru and Mexico and add to the construction of external validity.

Long-Term Effects of Temporary Incentives to Save:
Evidence from a Prize-Linked Savings Field Experiment (2020).  In a large field experiment in Mexico, we provide a temporary incentive to both open and use a savings account: specifically we offer prize-linked savings accounts with cash-prize lotteries, where lottery tickets are awarded as a function of savings balances. We find that 41% more accounts are opened in treatment branches than in control branches on average. Although the incentive to save is temporary as lotteries are only offered for two months, the new accounts continue to be used over time. After five years, clients who opened accounts in response to the lottery continue saving and making transactions at the same rates as those who opened accounts in control branches during the same months.

Air Conditioning and Inequality (2020). In this paper we use household-level microdata from 16 countries to characterize empirically the relationship between climate, income, and residential air conditioning. We show that both current and future air conditioner usage is concentrated among high-income households. Not only do richer countries have much more air conditioning than poorer countries, but within countries adoption is highly concentrated among high-income households. The pattern of adoption is particularly stark in relatively low-income countries like India, where we show that the vast majority of adoption between now and 2050 will be concentrated among the upper income tercile. We use our model to forecast future adoption, show how patterns vary across countries and income levels, and then discuss what these patterns mean for health, productivity, and educational inequality.

Effect of Inquiry and Problem Based Pedagogy on Learning: Evidence from 10 Field Experiments in Four Countries. This paper estimates the effect of inquiry-and problem-based pedagogy (IPP) on students’ mathematics and science test scores. IPP creates active problem-solving opportunities in settings that provide meaning to the child. Students learn by collaboratively solving real-life problems, developing explanations, and communicating ideas. We finds that after seven months IPP increased mathematics and science scores by 0.18 and 0.14 standard deviations, and that boys benefit more than girls.

Vulnerability and Clientelism (2020). This study argues that economic vulnerability causes citizens to participate in clientelism, a phenomenon with various pernicious consequences. We employ a RCT that reduced household vulnerability through constructing residential water cisterns in drought-prone areas of Brazil. This intervention significantly decreased requests for private goods from politicians, especially among citizens likely to be in clientelist relationships. We also show the intervention decreased votes for incumbent mayors. 

Government transparency and political clientelism: Evidence from randomized anti-corruption audits in Brazil We study whether anti-corruption  audits  reduce  the  incidence of vote buying and political clientelism in the context of Brazil’s municipal government anti-corruption program.  We observe a substantial 3.2 percentage point (52 percent) reduction in the probability that candidates engage in vote buying during  electoral  periods;  these  effects  persist  across  electoral terms.  

Mortality from Nestlé’s Marketing of Infant Formula in Low and Middle-Income Countries - We estimate the impact of the availability of infant formula on infant mortality in low and middle-income countries.