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ISSN 2183-0843
Working Paper No 1903
Fevereiro 2019

Resumo
The use of lab in the field experiments has increased dramatically, given benefits of studying relevant populations. Conducted in environments where researchers must relinquish the control a standard laboratory offers, they raise the specter of communication from past to future participants, posing problems for inference. While researchers may take steps to avoid spillovers, little is known about the mechanics of such spillovers in lab in the field settings, nor to what extent they may bias inference. In rural villages participating in public goods games in Rwanda, I recover estimates of these spillovers by matching villages on all available pre-study observables, comparing those with and without communication opportunities. I find communication led to substantial unanticipated increases in cooperation, driven by conditional cooperators. I conclude with advice to manage potential bias from spillovers.

Working Paper

ISSN 2183-0843
Working Paper No 1902
Janeiro 2019

Resumo

The political resource curse is the idea that natural resources can lead to the deterioration of public policies through corruption and rent-seeking by those closest to political power. One prominent consequence is the emergence of conflict. This paper takes this theory to the data for the case of Mozambique, where a substantial discovery of natural gas recently took place.
Focusing on the anticipation of a resource boom and the behavior of local political structures and communities, a large-scale field experiment was designed and implemented to follow the dissemination of information about the newly-discovered resources. Two types of treatments provided variation in the degree of dissemination: one with information targeting only local political leaders, the other with information and deliberation activities targeting communities at large. A wide variety of theory-driven outcomes is measured through surveys, behavioral activities, lab-in-the-field experiments, and georeferenced administrative data about local conflict.
Information given only to leaders increases elite capture and rent-seeking, while information and deliberation targeted at citizens increases mobilization and accountability-related outcomes, and decreases violence. While the political resource curse is likely to be in play, the dissemination of information to communities at large has a countervailing effect.

Working Paper

ISSN 2183-0843
Working Paper No 1901
Janeiro 2019

Resumo

This paper uses a quasi-natural experiment, the recent gold boom in Burkina Faso, to document the local impact of two alternative mining techniques: artisanal and industrial mines. Artisanal mines have a bad reputation. When these mines (managed in commons) compete for land with industrial mines (privatized), governments tend to favor industries. However, more than 100 million people depend on artisanal mines for their livelihoods. Our identification strategy exploits two sources of variation. The spatial variation comes from the exposure of households to different geological endowments, and the temporal variation comes from changes in the global gold price. We are the first to document the economic impact of artisanal mines. We show that a 1% increase in the gold price increases consumption by 0.15% for households neighboring artisanal mines. Opening an industrial mine, in contrast, has no impact on local consumption.

Working Paper

ISSN 2183-0843
Working Paper No 1804
Dezembro 2018

Resumo

This paper aims at investigating how the occupational placement of immigrants relative to their qualifications affect their self-selection. Using an administrative matched employer-employee data set for Portugal for the years 2002-2009, we first estimate the probability that an average worker from a particular country is overeducated, matched, or undereducated relative to the skill needs of the occupation he takes upon immigration. Second, using these estimated probabilities, we analyze how overeducation and appropriate skill-occupation matches affect selection of immigrants from 40 origin countries. The results suggest that overeducation leads to negative self-selection of immigrants into the Portuguese labor market. Furthermore, the evidence suggests that appropriate occupation-skill matches affect migration selection positively. These results imply that receiving countries’ selective policies aimed at attracting high skilled immigrants should also focus on reducing occupation-skill mismatch probably through degree recognition and standardization in collaboration with sending countries.

Working Paper

ISSN 2183-0843
Working Paper No 1803
Novembro 2018

Resumo

Illegal migration to Europe through the sea, though risky, remains one of the most popular migration options for many Sub-Saharan Africans. This study aims at improving our understanding of the determinants of the willingness to migrate illegally from West Africa to Europe. We implemented an incentivized lab-in-the field experiment in rural Gambia, the country with the highest rate of illegal migration to Europe in the region. Sampled male youths aged 15 to 25 were given hypothetical scenarios regarding the probability of dying en route to Europe, and of obtaining asylum or legal residence status after successful arrival. According to our data, potential migrants overestimate both the risk of dying en route to Europe, and the probability of obtaining legal residency status. The experimental results suggest that the willingness to migrate illegally is affected by information on the chances of dying en route and of obtaining a legal residence permit. Our estimates show that providing potential migrants with official numbers on the probability of obtaining a legal residence permit decreases their likelihood of migration by 2.88 percentage points (pp), while information on the risk of migrating increases their likelihood of migration by 2.29pp – although the official risk information provided may be regarded as a lower bound to actual mortality. Follow up data collected one year after the experiment show that the migration decisions reported in the lab experiment correlate well with actual migration decisions and intentions. Overall, our study indicates that the migration decisions of potential migrants are likely to actively respond to relevant information.

Working Paper

ISSN 2183-0843
Working Paper No 1803
Novembro 2018

Resumo

Illegal migration to Europe through the sea, though risky, remains one of the most popular migration options for many Sub-Saharan Africans. This study aims at improving our understanding of the determinants of the willingness to migrate illegally from West Africa to Europe. We implemented an incentivized lab-in-the field experiment in rural Gambia, the country with the highest rate of illegal migration to Europe in the region. Sampled male youths aged 15 to 25 were given hypothetical scenarios regarding the probability of dying en route to Europe, and of obtaining asylum or legal residence status after successful arrival. According to our data, potential migrants overestimate both the risk of dying en route to Europe, and the probability of obtaining legal residency status. The experimental results suggest that the willingness to migrate illegally is affected by information on the chances of dying en route and of obtaining a legal residence permit. Our estimates show that providing potential migrants with official numbers on the probability of obtaining a legal residence permit decreases their likelihood of migration by 2.88 percentage points (pp), while information on the risk of migrating increases their likelihood of migration by 2.29pp – although the official risk information provided may be regarded as a lower bound to actual mortality. Follow up data collected one year after the experiment show that the migration decisions reported in the lab experiment correlate well with actual migration decisions and intentions. Overall, our study indicates that the migration decisions of potential migrants are likely to actively respond to relevant information.

Working Paper

ISSN 2183-0843
Working Paper No 1801
Junho 2018

Resumo

In this paper, we study information sharing through text messages among rural Mozambicans with access to mobile money. For this purpose, we conducted a lab-in-the-field experiment involving exogeneously assigned information links. In the base game mobile money
users receive an SMS containing information on how to redeem a voucher for mobile money. They are then given an opportunity to share this information with other subjects. We find that participants have a low propensity to redeem the voucher. They nonetheless share the
information with others, and many subjects share information they do not use themselves, consistent with warm glow. We observe that there is more information sharing when communication is entirely anonymous, and we uncover no evidence of homophily in information sharing. We introduce various treatments: varying the cost of information sharing; being shamed for not sending vouchers; and allowing subjects to appropriate (part of) the value of the shared information. All these treatments decrease information sharing. The main implication is that, to encourage information sharing, the best is to keep it simple.

Paper

ISSN 2183-0843
Working Paper No 1705
Agosto 2017

Resumo

Investment in improved agricultural inputs is infrequent for smallholder farmers in Africa. One barrier may be limited access to formal savings. We designed and conducted a field experiment in rural Mozambique that randomized access to a savings account through mobile money to a sample of smallholder farmers. All subjects were given access to mobile money and information about fertilizer use. We also randomized whether closest farming friends were targeted by the same intervention. We find that the savings account increased savings, the probability of fertilizer use, by 31-36 pp, and the use of other agricultural inputs. We also show that the savings account increased household expenditures, in particular non-frequent ones. Our results suggest that the network intervention decreased social pressure to share resources and that the savings account protected farmers against this network pressure.

Working Paper

ISSN 2183-0843
Working Paper No 1704
Abril 2017

Resumo

Electoral fraud is a common problem in young democracies. Election observers constitute one possible remedy. Yet, quantitative evidence of the causal effects of observers is scarce. Data on the random assignment of observers during Mozambique’s 2009 general elections is used to estimate the impact that observers have on electoral results. We are able to distinguish between domestic observers that stayed in the same ballot table for the whole of the election day, who were deployed countrywide, and international observers that circulated across a number of ballot locations, assigned within selected districts. We show that the presence of domestic observers reduced voter turnout and increased the share of blank votes countrywide. This suggests a reduction of ballot fraud activities. For selected districts in which international observers were active findings are less clear, as we do not find fraud-reducing effects for any of the two types of observers. A possible interpretation is that local politicians anticipate the presence of international electoral observers in convenient districts.

Working Paper

ISSN 2183-0843
Working Paper No 1703
Abril 2017

Resumo

Bayesian updating remains the benchmark for dynamic modeling under uncertainty within economics. Recent theory and evidence suggest individuals may process information in a biased manner when it relates to personal characteristics or future life outcomes. Specifically, updating has been found to be symmetric, with good news receiving more weight than bad news. I put this theory and evidence to the test, by examining information processing across multiple contexts with varying stake conditions. I do not find that good news is over-weighted relative to bad news, but in fact, I find the opposite asymmetry. However these updating patterns are present more generally, including when news is neither good nor bad. While updating across all context and stake conditions is asymmetric and conservative, posteriors remain well approximated by those calculated using Bayes’ rule. I investigate further possible determinants of asymmetry and conservatism, finding that the former is sensitive to signal types and the latter is driven solely by non-updates. Most importantly these patterns are present across all contexts, cautioning against the interpretation of asymmetric updating or other deviations from Bayes’ rule as being motivated by psychological biases.

Working Paper

ISSN 2183-0843
Working Paper No 1702
Abril 2017

Resumo

This paper starts from a review of RCT studies in development economics, and documents many studies largely ignore attrition once attrition rates are found balanced between treatment arms. The paper analyzes the implications of attrition for the internal and external validity of the results of a randomized experiment with balanced attrition rates, and proposes a new method to correct for attrition bias. We rely on a 10-years longitudinal data set with a nal attrition rate of 10 percent, obtained after intensive tracking of migrants, and document the sensitivity of ITT estimates for schooling gains and labour market outcomes for a social program in Nicaragua. We nd that not including those found during the intensive tracking leads to an overestimate of the ITT effects for the target population by more than
35 percent, and that selection into attrition is driven by observable baseline characteristics. We propose to correct for attrition using inverse probability weighting with estimates of weights that exploit the similarities between missing individuals and those found during an intensive tracking phase. We compare these estimates with alternative strategies using regression adjustment, standard weights, bounds or proxy information.

Working Paper

ISSN 2183-0843
Working Paper No 1701
Março 2017
Revisto em Agosto 2018

Resumo

What is the role of international migrants and, more specifically, of migrant networks in shaping the quality of political institutions in migrant sending countries? Our theory proposes that migration might change individual social identities and in this way intrinsic motivation for political participation, while it may also improve knowledge about better quality political institutions. Hence, international migration might increase political awareness and participation both by migrants and by other individuals in their networks. To test this hypothesis, this paper uses several survey and behavioral measures related to political participation and electoral knowledge. These data were purposely collected around the time of the 2009 elections in Mozambique. The empirical results show that the number of migrants an individual is in close contact through regular chatting within a village significantly increase political participation of residents in that village – more so than family links to migrants. Our findings are consistent with both improved knowledge about political processes, and increased intrinsic motivation for political participation being transmitted through migrant networks.

Working Paper

Uma versão revista deste working paper foi publicada na revista científica World Development.

ISSN 2183-0843
Working Paper No 1602
Dezembro 2016

Resumo

Working Paper

ISSN 2183-0843
Working Paper No 1601
Abril 2016
Revisão Janeiro 2018

Resumo

What role do social networks play in determining migrant labor market outcomes? We examine this research question using a random survey of 1500 immigrants living in Ireland. We empirically test the hypothesis that immigrants with more contacts in the host country perform better in the labor market. Our empirical analysis confirms this prediction by focusing broadly on the relationship between migrants’ social networks and a variety of labor market outcomes (namely wages, employment, occupational choice and job security), innovatively relative to the existing literature. We find evidence that having one more close contact person in the host country is associated with an increase of nearly 100 euros in the average monthly net salary, and with a higher probability of having a permanent job contract. Network size also seems to have a positive impact in the probability of migrants entering low-skilled occupations, but no effect on high-skilled occupations. Our data is not strongly supportive of a network size effect on employment. Our results are robust to sample selection and other endogeneity concerns. Overall, this paper expands previous findings in the literature mostly focused on wages and employment, and concludes that networks may also provide job security to immigrants.

Working Paper

ISSN 2183-0843
Working Paper No 1503
Março 2015

Resumo

This study analyses the access and use of financial services by small business owners in the cities of Mozambique, as an important tool for boosting economic growth and diminishing inequality. It correlates owners’ and business characteristics with the probability of adopting Points-of-Sale (POS), Mobile Banking and Mobile Money in everyday transactions. The main findings highlight that what mostly affects the use of POS is the size of business and the volume of transactions (positively correlated with POS adoption), while using mobile phone technologies for payments predominantly depends on the owner’s age and whether he/she is a frequent cellphone user. Moreover, to increase the use of electronic means of payment it is necessary to increase financial literacy and improve the banking services.

Working Paper

ISSN 2183-0843
Working Paper No 1502
Abril 2015

Resumo

The objective of this work is to develop an operational tool to analyze exchange rate pressure in the context of Angola. The Angolan economy exhibits a number of relevant characteristics: a closed financial account, a partially controlled current account, a highly dollarized economy and exports (oil) price determined in World markets. These features have a direct effect on the demand of foreign currency and motivate their inclusion in the specification of a model for Angola. The model provides the rational for a measure of an exchange market rate pressure (EMP) index that contains exports changes, imports changes, the foreign interest rate and inflation and the change in foreign reserves corrected for a measure dollarization. The empirical performance new measure is comparable (slightly better) to the performance of the EMP indexes obtained in Eichengreen Rose and Wyplosz (1994) and Klassen and Jager (2011).

Working Paper

ISSN 2183-0843
Working Paper No 1501
Fevereiro 2015

Resumo

The study departs from two assumptions. First, it considers that organizations and their leadership are inherently paradoxical and that, in that sense, dealing with paradox is a necessary component of the leadership process. Second, it explores whether the paradoxes of leadership may manifest differently in different contexts. We explore the emergence of paradox in the leadership of Angolan organizations. Angola is an economy transitioning from a centrally-planned to a market mode, and this makes it a rich site for understanding the specificities of paradoxical processes in an under-researched, “rest of the world”, context. The findings of our inductive study led to the emergence of four interrelated paradoxes and highlight the importance of paradoxical work as a management requirement.

Working Paper

ISSN 2183-0843
Working Paper No 1402
Novembro 2014

Resumo

How do risk preferences affect migrant remittance behaviour? Examination of this relationship has only begun to be explored. Using a tailored representative survey of 1500 immigrants in the Greater Dublin Area, Ireland, we find a positive and significant relationship between risk aversion and migrant remittances. Risk-averse individuals are more likely to send remittances home and are, on average, likely to remit a higher amount, after controlling for a broad range of individual and group characteristics. The evidence we obtain is consistent with a “purchase of self-insurance” motive to remit in that we also find support for more remittances being sent by risk-averse immigrants who face higher wage risks and to individuals with more financial resources.

Working Paper

Este artigo foi publicado em Janeiro de 2016 no Oxford Economic Papers, Volume 68, Páginas 108–130. Encontre a versão publicada em inglês aqui.

ISSN 2183-0843
Working Paper No 1401
Maio 2014

Resumo

Are return migrants more entrepreneurial? Existing literature has not addressed how estimating the impact of return migration on entrepreneurship is affected by double unobservable migrant self-selection, both at the initial outward migration and at the final inward return migration stages. This paper exploits exogenous variation provided by the civil war and the incidence of agricultural plagues in Mozambique, as well as social unrest and other shocks in migrant destination countries. The results lend support to overall negative unobservable return migrant self-selection, which results in an under-estimation of the effects of return migration on entrepreneurial outcomes when using a ‘naïve’ estimator that does not control for self-selection at both the initial migration and at the final return migration stages.

Working Paper

Este artigo foi publicado em outubro 2017 no Oxford Bulletin of Economics and Statistics, Volume 79, Páginas 797-821. Encontre a versão publicada em inglês aqui.

ISSN 2183-0843
Working Paper No 1306
Dezembro 2013

Resumo

Do information flows matter for remittance behavior? We design and implement a randomized control trial to quantitatively assess the role of communication between migrants and their contacts abroad on the extent and value of remittance flows. In the experiment, a random sample of 1,500 migrants residing in Ireland was offered the possibility of contacting their networks outside the host country for free over a varying number of months. We find a sizable, positive impact of our intervention on the value of migrant remittances sent. Our results exclude that the remittance effect we identify is a simple substitution effect. Instead, our analysis points to this effect being a likely result of improved information via factors such as better migrant control over remittance use, enhanced trust in remittance channels due to experience sharing, or increased remittance recipients’ social pressure on migrants.

Working Paper

Este artigo foi publicado em fevereiro de 2018 no The World Bank Economic Review, Volume 32, Páginas: 203 – 219. Encontre a versão publicada em inglês aqui.

ISSN 2183-0843
Working Paper No 1305
Setembro 2013

Resumo

Vitamin A deficiency is a widespread public health problem in Sub- Saharan Africa. This paper analyses the impact of a food-based intervention to fight vitamin A deficiency using orange-fleshed sweet potato (OFSP). We conducted a randomized evaluation of OFSP-related training to female farmers in Mozambique, in which the treatment group was taught basic concepts of nutrition, and OFSP-planting and cooking skills. We found encouraging evidence of changes in behavior and attitudes towards OFSP consumption and planting, and considerable increases in nutrition-related knowledge, as well as knowledge on cooking and planting OFSP.

Transfira o PDF do Working Paper aqui

ISSN 2183-0843
Working Paper No 1303
Setembro 2013

Resumo

Voter education campaigns often aim to increase voter participation and political accountability. We follow randomized interventions implemented nationwide during the 2009 Mozambican elections using a free newspaper, leaflets and text messaging. We investigate whether treatment effects were transmitted through social networks (kinship and chatting) and geographical proximity. For individuals personally targeted by the campaign, we estimate the reinforcement effect of proximity to other targeted individuals. For untargeted individuals, we estimate the diffusion of the campaign depending on proximity to targeted individuals. We find evidence for both effects, similar across the different treatments and across the different connectedness measures. We observe that the treatments worked through networks by raising the levels of information and interest about the election, in line with the average treatment effects. However, differently from those average effects, we find negative network effects of voter education on voter participation. We interpret this result as a free riding effect, likely to occur for costly actions.

Working Paper

ISSN 2183-0843
Working Paper No 1302
Setembro 2013

Resumo

We investigate the determinants of giving in a lab-in-the-field experiment with large stakes. Study participants in urban Mozambique play dictator games where their counterpart is the closest person to them outside their household. Dictators share more with counterparts when they have the option of giving in kind (in the form of goods), compared to giving that must be in cash. Qualitative post-experiment responses suggest that this effect is driven by a desire to control how recipients use gifted resources. Standard economic determinants such as the rate of return to giving and the size of the endowment also affect giving, but the effects of even large changes in these determinants are significantly smaller than the effect of the in-kind option. Our results support theories of giving where the utility of givers depends on the composition (not just the level) of gift-recipient expenditures, and givers thus seek control over transferred resources.

Working Paper

Este artigo foi publicado como artigo principal no Journal of Economic Behavior & Organization in October 2015, Volume 118, Páginas 2-21. Poderá encontrar a versão publicada em inglês aqui.

ISSN 2183-0843
Working Paper No 1304
Setembro 2013

Resumo

African elections often reveal low levels of political accountability. We assess different forms of voter education during an election im Mozambique. Three interventions to providing information to voters and calling for their electoral participation were randomized: an SMS – based information campaingn, an SMS hotline for electoral misconduct, and the distribution of a free newspaper. To mesure impact, we look at official electoral results, reports by electoral observers, behavioral and survey data. We find positive effects of all treatments on voter turnout. We observe that the distribution of the newspaper led to more accountability-based participation and to a decrease in an electoral problems.

Working Paper

Este artigo foi publicadol no Review of Economics and Statistics Maio 2017, Volume 99(2), Páginas 185-200. Poderá encontrar a versão publicada em inglês aqui.

ISSN 2183-0843
Working Paper No 1301
Setembro 2013

Resumo

The limitations of access to finance in Africa, together with the recent boom in cell phone use in that continent, created high expectations regarding the introduction of mobile money in many African countries. The success story of M-PESA in Kenya raised the bar further. We designed and conducted a field experiment to assess the impact of randomized mobile money dissemination in rural Mozambique. For this purpose we benefit from the fact that mobile money was only recently launched in the country, allowing for the identification of a pure control group. This paper reports on the first results of this ongoing project after the first wave of dissemination efforts in rural locations, which included the recruitment and training of mobile money agents, community meetings and theaters, as well as individual rural campaigning. Administrative and behavioral data both show clear adherence to the services in the treatment group. Financial literacy and trust outcomes are also positively affected by the treatment. We present behavioral evidence that the marginal willingness to remit was increased by the availability of mobile money. Finally, we observe a tendency for mobile money to substitute traditional alternatives for both savings and remittances.

Working Paper