Journal of Labor Economics202240(S1), S293-S340open access
We study the impact of artificial intelligence (AI) on labor markets using establishment-level data on the near universe of online vacancies in the United States from 2010 onward. There is rapid growth in AI-related vacancies over 2010–18 that is driven by establishments whose workers engage in tasks compatible with AI’s current capabilities. As these AI-exposed establishments adopt AI, they simultaneously reduce hiring in non-AI positions and change the skill requirements of remaining postings. While visible at the establishment level, the aggregate impacts of AI-labor substitution on employment and wage growth in more exposed occupations and industries is currently too small to be detectable.
American Economic Review200797(3), 916-943open access
We develop a tractable framework for the analysis of the relationship between contractual incompleteness, technological complementarities, and technology adoption. In our model, a firm chooses its technology and investment levels in contractible activities by suppliers of intermediate inputs. Suppliers then choose investments in noncontractible activities, anticipating payoffs from an ex post bargaining game. We show that greater contractual incompleteness leads to the adoption of less advanced technologies, and that the impact of contractual incompleteness is more pronounced when there is greater complementary among the intermediate inputs. We study a number of applications of the main framework and show that the mechanism proposed in the paper can generate sizable productivity differences across countries with different contracting institutions, and that differences in contracting institutions lead to endogenous comparative advantage differences.
Journal of Economic Literature202563(2), 637-692open access
This paper proposes a new framework for studying the interplay between culture and institutions. We interpret culture as a repertoire, consisting of (cultural) attributes and allowing rich cultural responses to political changes. Combinations of attributes produce cultural configurations, which provide social meaning, coordination and political justification. Our framework has several distinctive features. First, it proposes a “systems approach” to culture: the meaning and function of attributes are determined within the whole configuration and political equilibrium. Second, it emphasizes discontinuous or “saltational” changes in culture—rather than gradual, evolutionary changes—as attributes are reconnected and acquire new meanings in response to evolving circumstances and as outcomes in ongoing “cultural struggles”. Third, our framework puts the spotlight on how fluidly different cultures can respond to conditions, depending on the nature of their attributes and constraints on their connections. Finally, it enriches the study of the co-determination of political, institutional and cultural outcomes.
Review of Economic Studies201987(2), 537-581open access
We document that the spread of the Mafia in Sicily at the end of the 19th century was in part caused by the rise of socialist Peasant Fasci organizations. In an environment with weak state presence, this socialist threat triggered landowners, estate managers, and local politicians to turn to the Mafia to resist and combat peasant demands. We show that the location of the Peasant Fasci is significantly affected by a severe drought in 1893, and using information on rainfall, we estimate the impact of the Peasant Fasci on the location of the Mafia in 1900. We provide extensive evidence that rainfall before and after this critical period has no effect on the spread of the Mafia or various economic and political outcomes. In the second part of the article, we use this source of variation in the strength of the Mafia in 1900 to estimate its medium-term and long-term effects. We find significant and quantitatively large negative impacts of the Mafia on literacy and various public goods in the 1910s and 20s. We also show a sizable impact of the Mafia on political competition, which could be one of the channels via which it affected local economic outcomes. We document negative effects of the Mafia on longer-term outcomes (in the 1960s, 70s, and 80s) as well, but these are in general weaker and often only marginally significant. One exception is its persistent and strong impact on political competition.
We develop a tractable model of endogenous production networks. Each one of a number of products can be produced by combining labor and an endogenous subset of the other products as inputs. Different combinations of inputs generate (prespecified) levels of productivity and various distortions may affect costs and prices. We establish the existence and uniqueness of an equilibrium and provide comparative static results on how prices and endogenous technology/input choices (and thus the production network) respond to changes in parameters. These results show that improvements in technology (or reductions in distortions) spread throughout the economy via input–output linkages and reduce all prices, and under reasonable restrictions on the menu of production technologies, also lead to a denser production network. Using a dynamic version of the model, we establish that the endogenous evolution of the production network could be a powerful force towards sustained economic growth. At the root of this result is the fact that the arrival of a few new products expands the set of technological possibilities of all existing industries by a large amount—that is, if there are n products, the arrival of one more new product increases the combinations of inputs that each existing product can use from 2 n −1 to 2 n , thus enabling significantly more pronounced cost reductions from choice of input combinations. These cost reductions then spread to other industries via lower input prices and incentivize them to also adopt additional inputs.
Review of Financial Studies201831(1), 1-42open access
Unprecedented street protests brought down Mubarak's government and ushered in an era of competition between three rival political groups in Egypt. Using daily variation in the number of protesters, we document that more intense protests are associated with lower stock market valuations for firms connected to the group currently in power relative to non-connected firms, but have no impact on the relative valuations of firms connected to rival groups. These results suggest that street protests serve as a partial check on political rent-seeking. General discontent expressed on Twitter predicts protests but has no direct effect on valuations.
American Economic Review2016106(5), 61-67open access
Robert Gordon's The Rise and Fall of American Economic Growth compellingly shows how technical innovation, stimulated by the country's institutions, has radically improved the living standards of the citizens of the US. We conduct an empirical investigation of the impact of the capacity of the US state, as proxied by the presence of post offices, on innovation. We show that there is a strong association between the number of post offices in a county and patenting activity. Our evidence suggests that part of story of US innovation is the capacity and reach of the US state.
Review of Economic Studies200875(4), 987-1009open access
We study the formation of a ruling coalition in non-democratic societies where institutions do not enable political commitments. Each individual is endowed with a level of political power. The ruling coalition consists of a subset of the individuals in the society and decides the distribution of resources. A ruling coalition needs to contain enough powerful members to win against any alternative coalition that may challenge it, and it needs to be self-enforcing, in the sense that none of its subcoalitions should be able to secede and become the new ruling coalition. We present both an axiomatic approach that captures these notions and determines a (generically) unique ruling coalition and the analysis of a dynamic game of coalition formation that encompasses these ideas. We establish that the subgame-perfect equilibria of the coalition formation game coincide with the set of ruling coalitions resulting from the axiomatic approach. A key insight of our analysis is that a coalition is made self-enforcing by the failure of its winning subcoalitions to be self-enforcing. This is most simply illustrated by the following example: with “majority rule”, two-person coalitions are generically not self-enforcing and consequently, three-person coalitions are self-enforcing (unless one player is disproportionately powerful). We also characterize the structure of ruling coalitions. For example, we determine the conditions under which ruling coalitions are robust to small changes in the distribution of power and when they are fragile. We also show that when the distribution of power across individuals is relatively equal and there is majoritarian voting, only certain sizes of coalitions (e.g. with majority rule, coalitions of size 1, 3, 7, 15, etc.) can be the ruling coalition.
American Economic Review2015105(8), 2364-2409open access
We study the direct and spillover effects of local state capacity in Colombia. We model the determination of state capacity as a network game between municipalities and the national government. We estimate this model exploiting the municipality network and the roots of local state capacity related to the presence of the colonial state and royal roads. Our estimates indicate that local state capacity decisions are strategic complements. Spillover effects are sizable, accounting for about 50 percent of the quantitative impact of an expansion in local state capacity, but network effects driven by equilibrium responses of other municipalities are much larger.
American Economic Review2012102(1), 131-166open access
This paper introduces endogenous and directed technical change in a growth model with environmental constraints and limited resources. A unique final good is produced by combining inputs from two sectors. One of these sectors uses "dirty" machines and thus creates environmental degradation. Research can be directed to improving the technology of machines in either sector. We characterize dynamic tax policies that achieve sustainable growth or maximize intertemporal welfare, as a function of the degree of substitutability between clean and dirty inputs, environmental and resource stocks, and cross-country technological spillovers. We show that: (i) in the case where the inputs are sufficiently substitutable, sustainable long-run growth can be achieved with temporary taxation of dirty innovation and production; (ii) optimal policy involves both "carbon taxes" and research subsidies, so that excessive use of carbon taxes is avoided; (iii) delay in intervention is costly: the sooner and the stronger is the policy response, the shorter is the slow growth transition phase; (iv) the use of an exhaustible resource in dirty input production helps the switch to clean innovation under laissez-faire when the two inputs are substitutes. Under reasonable parameter values (corresponding to those used in existing models with exogenous technology) and with sufficient substitutability between inputs, it is optimal to redirect technical change towards clean technologies immediately and optimal environmental regulation need not reduce long-run growth. We also show that in a two-country extension, even though optimal environmental policy involves global policy coordination, when the two inputs are sufficiently substitutable environmental regulation only in the North may be sufficient to avoid a global disaster.