NBER Working Papers by Massimo Morelli

Contact and additional information for this authorAll publicationsWorking Papers only

Working Papers

April 2013The Geography of Inter-State Resource Wars
with Francesco Caselli, Dominic Rohner: w18978
We establish a theoretical as well as empirical framework to assess the role of resource endowments and their geographic location for inter-State conflict. The main predictions of the theory are that conflict tends to be more likely when at least one country has natural resources; when the resources in the resource-endowed country are closer to the border; and, in the case where both countries have natural resources, when the resources are located asymmetrically vis-a-vis the border. We test these predictions on a novel dataset featuring oilfield distances from bilateral borders. The empirical analysis shows that the presence and location of oil are significant and quantitatively important predictors of inter-State conflicts after WW2.
February 2012Signalling, Incumbency Advantage, and Optimal Reelection Thresholds
with Francesco Caselli, Thomas E. Cunningham, Inés Moreno de Barreda: w17833
Much literature on political behavior treats politicians as motivated by reelection, choosing actions to signal their types to voters. We identify two novel implications of models in which signalling incentives are important. First, because incumbents only care about clearing a reelection hurdle, signals will tend to cluster just above the threshold needed for reelection. This generates a skew distribution of signals leading to an incumbency advantage in the probability of election. Second, voters can exploit the signalling behavior of politicians by precommitting to a higher threshold for signals received. Raising the threshold discourages signalling effort by low quality politicians but encourages effort by high quality politicians, thus increasing the separation of signals and improving...
November 2003Self Enforcing Voting in International Organizations
with Giovanni Maggi: w10102
Some international organizations are governed by unanimity rule, some others by a majority system. Still others have moved from one system to the other over time. The existing voting models, which generally assume that decisions made by voting are perfectly enforceable, have a difficult time explaining the observed variation in governance mode, and in particular the widespread occurrence of the unanimity system. We present a model whose main departure from standard voting models is that there is no external enforcement mechanism: each country is sovereign and cannot be forced to follow the collective decision, or in other words, the voting system must be self-enforcing. The model yields unanimity as the optimal system for a wide range of parameters, and delivers rich predictions on the var...
October 2001Bad Politicians
with Francesco Caselli: w8532
We present a simple theory of the quality (competence and honesty) of elected officials. Our theory offers four main insights. Low-quality citizens have a 'comparative advantage' in pursuing elective office, because their market wages are lower than those of high-quality citizens (competence), and/or because they reap higher returns from holding office (honesty). Hence, voters may find themselves supply constrained of high-quality candidates. Second, bad politicians generate negative externalities for good ones, making their rewards from office increasing in the average quality of office holders. This leads to multiple equilibria in quality. Third, incumbent policymakers can influence the rewards of future policymakers, leading to path dependence in quality: bad governments saw the seeds f...

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