Working papers results

A decision maker can experiment on up to two alternatives simultaneously over time. One and only one of these alternatives can produce successes, according to a Poisson process with known arrival rate; but there is uncertainty as to which alternative is the profitable one. The decision maker only observes the outcomes of the alternatives chosen, and choosing each alternative entails a cost. Simultaneous experimentation involves higher costs but can produce more data. At the same time, since the alternatives are negatively correlated, the outcomes of either one are informative about the other. If the costs are high and she is sufficiently impatient, the decision maker never experiments on both alternatives at once. Otherwise, if she starts with a single alternative that produces no successes, she becomes gradually pessimistic and eventually takes on the other alternative while keeping the first one - despite the higher costs and the negative correlation.

A model of 'harassment bribes,' paid for services one is entitled to, is developed to analyze
the proposal to legalize paying these bribes while increasing fines on accepting them.
We explore performance as regards corruption deterrence and public service provision. Costs of verifying reports make the scheme more effective against larger bribes and where institutions' quality is higher. A modified scheme, where immunity is conditional on reporting, addresses some key objections. The mechanism works better against more distortionary forms of corruption than harassment bribes, provided monetary rewards can compensate bribers for losing the object of the corrupt exchange. Results highlight strong complementarities with policies aimed at improving independence and accountability of law enforcers.

A decision maker faces an unobserved state of nature. She updates her prior on the state based on the realizations of a signal. In this note, we show that the expected posterior on any given state, taking expectation under the conditional distribution of the signal on this same state, is never lower than the prior on said state. In other words, the expected posterior probability on the true state is never lower than the prior on this state, regardless of what the true state is.

This paper is the first attempt, to the best of our knowledge, to study the impact of a carbon tax by means of a heterogeneous agents model. The objectives of the paper are two: i) To assess how the results of a representative agent model compare to those coming from a model accounting for heterogeneity across agents when evaluating aggregate economic and environmental impacts of a carbon tax; ii) To assess the distributional implications of a carbon tax and how they can be mitigated through different recycling schemes. We find that heterogeneous agents models may deliver different results from those derived using a representative agent model, the main tool used to guide policy making so far. In particular, we find evidence of a double dividend for several recycling schemes and carbon taxes as high as 20% of the energy price. In addition, we find the potential for redistributive channels related to carbon policies that can only be appreciated applying this type of modeling.

What are the political consequences of introducing de jure political equality? Does it change
patterns of political representation and the identity of elected legislators? This paper uses an important electoral reform passed in 1912 in Italy to provide evidence on these questions. The reform trebled the electorate (from slightly less than three million to 8.650.000) leaving electoral rules and district boundaries unchanged. By exploiting differences in enfranchisement rates across electoral districts we identify the effect of franchise extension on various political outcomes. Enfranchisement increased the vote share of left-wing social reformers but had no impact on their parliamentary representation, no impact on parliamentary representation of aristocracy and traditional elites and no effect on political competition. We show that left-wing parties decreased their vote shares and were systematically defeated in key swing districts. We document elite's effort to minimize the political impact of the reform and, in particular, we show that the Vatican's secret involvement in the post-reform electoral campaign had a substantial impact on voting results, although formerly and newly enfranchised voters were equally affected. We relate our results to economic theories of democratization, which appear to be only partially compatible with our evidence.

We provide evidence on whether providing university students with feedback on their past
exam performance affects their future exam performance. Our identification strategy exploits a natural experiment in a leading UK university where different departments have historically
different rules on the provision of feedback to their students. We find the provision of feedback has a positive effect on students' subsequent test scores: the mean impact corresponds to 13% of a standard deviation in test scores. The impact of feedback is stronger for more able students and for students who have less information to start with about the academic environment, while no subset of individuals is found to be discouraged by feedback. Our findings suggest that students have imperfect information on how their effort translates into test scores and that the provision of feedback might be a cost effective means to increase students' exam performance.

We analyze the value of information in the market for corporate control. The raider and the shareholders are privately and imperfectly informed about the post-takeover value of the firm. We show that public information provision reduces the dispersion of the shareholders' beliefs resulting in a transfer of surplus from the raider to the shareholders. What is more, if the raider is privately informed all his private information is revealed through the price offer, hence he prefers not to acquire private information, provided that the shareholders do not engage in information acquisition. The target shareholders, on the other hand, have incentives to acquire information-solicit a fairness opinion-after the raider makes a price offer. However, when both parties have access to an information market, they both have incentives to acquire information.

We view economic time series as the result of a cascade of shocks occurring at different times and different frequencies (scales). We suggest that economic relations that are found to be elusive when using raw data may hold true for different layers (details) in the cascade of economic shocks. This observation leads to a notion of a scale-specific predictability. Using direct extraction of the details and two-way aggregation, we provide strong evidence of risk compensations in market returns, as well as of an unusually clear link between macroeconomic uncertainty and uncertainty in financial markets, at frequencies lower than the business cycle.

The paper aims to analyze the effects of plague on the long-term development of Italian cities, with particular attention to the 1629-30 epidemic. By using a new dataset on plague mortality rates in 49 cities covering the period 1575-1700 ca., an economic geography model verifying the existence of multiple equilibria is estimated. It is found that cities affected only by the 1629-30 plague recovered in the short run, whereas cities affected by both the 1575-77 and 1629-30 epidemic show persistent decline in the long run. This new finding contrasts with previous literature and is hence interpreted in the light of the new concept of "urban frailty".