Skip to main content
Open Access Publications from the University of California

The CEGA Working Paper Series showcases ongoing and completed research by faculty affiliates of the Center. CEGA Working Papers employ rigorous evaluation techniques to measure the impact of large-scale social and economic development programs, and are intended to encourage discussion and feedback from the global development community.

Cover page of Scabs: The Social Suppression of Labor

Scabs: The Social Suppression of Labor


Social norms have the potential to alter the functioning of economic markets. We test whether norms shape the aggregate labor supply curve by preventing workers from supplying labor at wage cuts—leading decentralized individuals to implicitly behave as a cartel to maintain wage floors in their local labor markets. We partner with 183 existing employers, who offer jobs to 502 workers in informal spot labor markets in India. Unemployed workers are privately willing to accept jobs below the prevailing wage, but rarely do so when this choice is observable to other workers. In contrast, social observability does not affect labor supply at the prevailing wage. Workers give up 49% of average weekly earnings to avoid being seen as breaking the social norm. In addition, workers pay to punish anonymous laborers who have accepted wage cuts—indicating that cartel behavior is reinforced through the threat of social sanctions. Punishment occurs for workers in one’s own labor market and for those in distant regions, suggesting the internalization of norms in moral terms. Finally, consistent with the idea that norms could have aggregate implications, measures of social cohesion correlate with downward wage rigidity and business cycle volatility across India.

Cover page of Encouraging​ ​Fertilizer​ ​Adoption​ ​through Risk-Free​ ​Sales​ ​Offers

Encouraging​ ​Fertilizer​ ​Adoption​ ​through Risk-Free​ ​Sales​ ​Offers


Only around 8 percent of farmers in Uganda use fertilizer, even though most of the country’s soil is nitrogen deficient and fertilizer is typically profitable when it is used. A variety of constraints may contribute to low fertilizer usage, such as: lack of liquidity at planting season, weather risk, lack of access to fertilizer, lack of training, and risk of purchasing counterfeit fertilizer. In this experiment we test the efficacy of a “risk-free sample offer” sales model to increase fertilizer adoption and to better understand the constraints farmers face. The risk-free sample offer provided farmers with enough fertilizer for 1/8 of an acre. The sales agents then assisted the farmers in staking off a 1/8 acre plot to test the fertilizer on and a separate 1/8 acre plot to serve as a comparison. The farmers agreed to pay for the fertilizer after harvest, but only if the increased profit from the fertilized plot was more than the value of the fertilizer. We explained we would only sell farmers fertilizer for the following season if they paid for their risk-free sample. Therefore, the ability to do future business with the sales agent provided incentive for the farmer to make the payment.

We tested the sale offer in Mityana district using a randomized control trial of 333 treatment farmers and 352 control farmers from September 2016 to April 2017. The risk-free sample offer increased initial uptake of fertilizer by 74 percentage points over the control group. Unfortunately, the region suffered a very serious drought which led many farmers to have a very low harvest (and sometimes none). The drought persisted into the following planting season, which discouraged many of the farmers from investing in fertilizer. Regardless, 34 percent repaid some or all of the fertilizer from the risk free purchase even though most were not required to, and 24 treatement farmers purchased fertilizer for the following season (21 percent above the control group).

Despite the severe drought, the experiment demonstrated that the risk-free sample offer generated considerable demand for fertilizer. We also found evidence of spillover effects to such as control farmers who initially turned declined to purchased fertilizer in the first round, but indicated interested in the second round. Ugandan farmers also exhibited high trustworthiness, with many repayments from farmers who were not required to repay after the drought prevented the fertilizer from turning a profit.

Future interventions to improve fertilizer adoption should consider using a multi-pronged approach that addresses weather risk, training, fertilizer access, and price risk simultaneously. The document concludes with some lessons learned and recommendations for practitioners interested in exploring this sales offer further.

Cover page of The Limits of Commitment: Who Benefits from Illiquid Savings Products?

The Limits of Commitment: Who Benefits from Illiquid Savings Products?


Working with a private bank in Ghana, this study examines the impacts of a commitment savings product designed to help clients taking repeated overdrafts break their debt cycles. Overall, the product significantly increased savings with the bank without increasing overdrafts. However, after accounting for other sources of savings, the study finds that clients with above-median baseline overdraft histories do not accrue new savings during the commitment period. Rather, they draw down other savings to offset the committed amount and take on new debt. In contrast, individuals with below-median overdraft histories significantly increase savings during and after the commitment period.

Cover page of The Effects of Fuel-Efficient Cookstoves on Fuel Use, Particulate Matter, and Cooking Practices: Results from a Randomized Trial in Rural Uganda

The Effects of Fuel-Efficient Cookstoves on Fuel Use, Particulate Matter, and Cooking Practices: Results from a Randomized Trial in Rural Uganda


Smoky cookfires contribute to global climate change and kill approximately four million people annually. While many studies have examined the effects of fuel-efficient cookstoves, this study was the first to do so while selling stoves at market prices. After introducing a fuel-efficient cookstove, fuelwood use and household air particulates declined by 12% and by smaller percentages after adjusting for observer-induced bias, or the Hawthorne effect. These reductions were less than laboratory predictions and fell well short of World Health Organization pollution targets. Even when introducing a second stove, most households continued to use their traditional stoves for most cooking.

Cover page of Extreme Temperatures and Time-Use in China

Extreme Temperatures and Time-Use in China


How do people in developing countries respond to extreme temperatures? Using individual-level panel data over two decades and relying on plausibly exogenous variation in weather, we estimate how extreme temperatures affect time use in China. Extreme temperatures reduce time spent working, and this effect is largest for female farmers. Hot days reduce time spent by women on outdoor chores, but we find no such effects for men. Finally, hot days dramatically reduce time spent on childcare, reflecting large effects on home production. Taken together, our results suggest time use is an important margin of response to extreme temperatures.

Cover page of How Research Affects Policy: Experimental Evidence from 2,150 Brazilian Municipalities

How Research Affects Policy: Experimental Evidence from 2,150 Brazilian Municipalities


This paper investigates if research findings change political leaders’ beliefs and cause policy change. Collaborating with the National Confederation of Municipalities in Brazil, we work with 2,150 municipalities and the mayors who control their policies. We use experiments to measure mayors’ demand for research information and their response to learning research findings. In one experiment, we find that mayors and other municipal officials are willing to pay to learn the results of impact evaluations, and update their beliefs when informed of the findings. They value larger-sample studies more, while not distinguishing on average between studies conducted in rich and poor countries. In a second experiment, we find that informing mayors about research on a simple and effective policy (reminder letters for taxpayers) increases the probability that their municipality implements the policy by 10 percentage points. In sum, we provide direct evidence that providing research information to political leaders can lead to policy change. Information frictions may thus help explain failures to adopt effective policies.

Cover page of The agricultural wage gap within rural villages 

The agricultural wage gap within rural villages 


We use a unique dataset on daily labor-market outcomes for Indian casual workers to study labor reallocation between agricultural and non-agricultural activities within rural areas. We use workers who switch sectors during a period of one to two weeks to estimate an agricultural wage gap that cannot be due to selection on unobservable characteristics. Workers can obtain 21 percent higher wages by taking non-agricultural jobs, many of which are available inside their villages. Surveys reveal that non-agricultural jobs are less preferred because they are harder, suggesting that the agricultural wage gap in rural areas might reflect a compensating differential.

Cover page of Endogenous Information Sharing and the Gains from Using Network Information to Maximize Technology Adoption

Endogenous Information Sharing and the Gains from Using Network Information to Maximize Technology Adoption


Can agents in a social network be induced to obtain information from outside their peer groups? Using a field experiment in rural Bangladesh, we show that demonstration plots in agriculture - a technique where the first users of a new variety cultivate it in a side-by-side comparison with an existing variety - facilitate social learning by inducing conversations and information sharing outside of existing social networks. We compare these improvements in learning with those from seeding new technology with more central farmers in village social networks. The demonstration plots - when cultivated by randomly selected farmers - improve knowledge by just as much as seeding with more central farmers. Moreover, the demonstration plots only induce conversations and facilitate learning for farmers that were unconnected to entry points at baseline. Finally, we combine this diffusion experiment with an impact experiment to show that both demonstration plots and improved seeding transmit information to farmers that are less likely to benefit from the new innovation.

Cover page of The Effects of Income Transparency on Well-Being- Evidence from a Natural Experiment

The Effects of Income Transparency on Well-Being- Evidence from a Natural Experiment


In 2001, Norwegian tax records became easily accessible online, allowing everyone in the country to observe the incomes of everyone else. According to the income comparisons model, this change in transparency can widen the gap in well-being between richer and poorer individuals. We test this hypothesis using survey data from 1985–2013. Using multiple identification strategies, we show that the higher transparency increased the gap in happiness between richer and poorer individuals by 29%, and it increased the life satisfaction gap by 21%. We provide suggestive evidence that some, although probably not all, of this effect relates to changes in self-perceptions of relative income. We provide back-of-the-envelope estimates of the importance of income comparisons, and discuss implications for the ongoing debate on transparency policies.

Cover page of Estimating spillovers using imprecisely measured networks

Estimating spillovers using imprecisely measured networks


In many experimental contexts, whether and how network interactions impact the outcome of interest for both treated and untreated individuals are key concerns. Networks data is often assumed to perfectly represent these possible interactions. This paper considers the problem of estimating treatment eects when measured connections are, instead, a noisy representation of the true spillover pathways. We show that existing methods, using the potential outcomes framework, yield biased estimators in the presence of this mismeasurement. We develop a new method, using a class of mixture models, that can account for missing connections and discuss its estimation via the Expectation-Maximization algorithm. We check our method's performance by simulating experiments on real network data from 43 villages in India. Finally, we use data from a previously published study to show that estimates using our method are more robust to the choice of network measure.