Current Position
Professor of Economics, New York University in Abu Dhabi  

Editorial Positions
Main research interests
(i) evolution of cooperation, (ii) conflict resolution, (iii) determinants of anti-social and pro-social behavior, (iv) gender differences in competitiveness.  

Latest working papers
"The ghost of institutions past: history as an obstacle to fighting tax evasion" (w. Aaron Kamm and Christian Koch) (2017) NYU Abu Dhabi WP #008.

AbstractIf taxpayers believe past rates of compliance are indicative of the future, traditional 
measures for combating tax evasion can be compromised. We present evidence from a 
novel laboratory experiment with strategic complementarities showing that a history 
of low compliance can render a major institutional reform ineffective at reducing 
tax evasion. The experimental treatments manipulate the history of tax compliance 
by varying the percentage of tax revenue embezzled by a ‘politician’ – our measure 
of ‘institutional quality’. We show that tax compliance is substantially higher in 
good-quality than bad-quality institutions when there is no history of tax evasion. 
When a bad-quality institution is replaced with a good-quality one, however, tax 
compliance remains low, as if the institutional change had not occurred. The reason 
is that the institutional change leaves expectations about future compliance largely 
unaffected. A history of high-quality institutions, on the other hand, shields tax 
compliance only partly from institutional deterioration. We discuss reasons for this, 
policy implications of our findings and evidence that a society-wide poll can assist 
in overcoming the ‘ghost of institutions past’.

"Are the rich more selfish than the poor, or do they just have more money? A natural field experiment" (w. James Andreoni and Jan Stoop) (2017) NBER Working paper #23229. [You can read more about it at The Conversation, Observer, and hear about it at a Freakonomics Radio special]

AbstractThe growing concentration of resources among the rich has re-ignited a discussion about whether the rich are more selfish than others. While many recent studies show the rich behaving less prosocially, endogeneity and selection problems prevent safe inferences about differences in social preferences. We present new evidence from a natural field experiment in which we “misdeliver” envelopes to rich and poor households in a Dutch city, varying their contents to identify motives for returning them. Our raw data indicate the rich behave more pro-socially. Controlling for pressures associated with poverty and the marginal utility of money, however, we find no difference in social preferences. The primary distinction between rich and poor is simply that the rich have more money.

Latest publications
"Emirati women do not shy away from competition: Evidence from a patriarchal society in transition" (w. Dariel Aurelie, Curtis Kephart and Christina Zenker) Journal of the Economic Science Association 3(2), 121-136. [NOTE: This study includes an exhaustive survey of all published work on gender differences in competitiveness]

AbstractWe explore gender attitudes towards competition in the United Arab Emirates – a traditionally patriarchal society which in recent times has adopted numerous policies to empower women and promote their role in the labor force. The experimental treatments vary whether individuals compete in single-sex or mixed-sex groups. In contrast to previous studies, women in our sample are not less willing to compete than men. In fact, once we control for individual performance, Emirati women are more likely to select into competition. Our analysis shows that neither women nor men shy away from competition, and both compete more than what would be optimal in monetary terms as the fraction of men in their group increases. We offer a detailed survey of the literature and discuss possible reasons for the lack of gender differences in our experiment.

"Normative conflict and the limits of self-governance Gangadharan Lata, and Marie-Claire Villeval). 
European Economic Review (2017) 100, 143–156.

AbstractMechanisms to overcome social dilemmas provide incentives to maximize efficiency. However, often – such as when agents are heterogeneous – there is a trade-off between efficiency and equality – a normative conflict – which is overlooked. Agents’ concerns for equality in such instances can limit the ability of mechanisms to promote efficiency. We provide evidence for this from a public good experiment using a simple mechanism allowing individuals to communicate periodically with other group members and reward them for their actions. We show that, in homogeneous populations – where there is no conflict between efficiency and equality – the mechanism permits groups to obtain maximum efficiency. This is not the case in heterogeneous populations despite the fact that individuals could use rewards to resolve the normative conflict. Although almost all heterogeneous groups agree to follow specific contribution rules with positive contributions, most of them either prioritize equality over efficiency or strike a compromise between the two. These findings suggest normative conflict can be difficult to overcome, imposing limits on the ability of heterogeneous populations to reach efficient outcomes through self-governance. 

"Altruistic punishment does not increase with the severity of norm violations in the field" (w. Loukas Balafoutas and Bettina Rockenbach). Nature Communications (2016) 7, 13327 doi:10.1038/ncomms13327. [You can read more about this at The National]

AbstractThe degree of human cooperation among strangers is a major evolutionary puzzle. A prominent explanation is that cooperation is maintained because many individuals have a predisposition to punish those violating group-beneficial norms. A critical condition for cooperation to evolve in evolutionary models is that punishment increases with the severity of the violation. Here we present evidence from a field experiment with real-life interactions that, unlike in lab experiments, altruistic punishment does not increase with the severity of the violation, regardless of whether it is direct (confronting a violator) or indirect (withholding help). We also document growing concerns for counter-punishment as the severity of the violation increases, indicating that the marginal cost of direct punishment increases with the severity of violations. The evidence suggests that altruistic punishment may not provide appropriate incentives to deter large violations. Our findings thus offer a rationale for the emergence of formal institutions for promoting large-scale cooperation among strangers.

Office hours 
Tuesday and Thursday, 9-10 am
For meetings outside these hours, please send me an email.

Office location
NYU Abu Dhabi, Saadiyat Island, Building A5, Office 1143

This website was (partly) updated on: Dec 5, 2017