Working papers results

We prove that a subtle but substantial bias exists in a standard measure of the conditional dependence of present outcomes on streaks of past outcomes in sequential data. The magnitude of this novel form of selection bias generally decreases as the sequence gets longer, but increases in streak length, and remains substantial for a range of sequence lengths often used in empirical work. The bias has important implications for the literature that investigates incorrect beliefs in sequential decision making - most notably the Hot Hand Fallacy and the Gambler's Fallacy. Upon correcting for the bias, the conclusions of prominent studies in the hot hand fallacy literature are reversed. The bias also provides a novel structural explanation for how belief in the law of small numbers can persist in the face of experience.

We study optimal selling strategies of a seller who is poorly informed about the buyer's value for the object. When the maxmin seller only knows that the mean of the distribution of the buyer's valuations belongs to some interval then nature can keep him to payoff zero no matter how much information the seller has about the mean. However, when the seller has information about the mean and the variance, or the mean and the upper bound of the support, the seller optimally commits to a randomization over prices and obtains a strictly positive payoff. In such a case additional information about the mean and/or the variance affects his payoff.

This paper proposes a Bayesian estimation framework for a typical multi-factor model with timevarying risk exposures to macroeconomic risk factors and corresponding premia to price U.S. publicly traded assets. The model assumes that risk exposures and idiosynchratic volatility follow a break-point latent process, allowing for changes at any point on time but not restricting them to change at all points. The empirical application to 40 years of U.S. data and 23 portfolios shows that the approach yields sensible results compared to previous two-step methods based on naive recursive estimation schemes, as well as a set of alternative model restrictions. A variance decomposition test shows that although most of the predictable variation comes from the market risk premium, a number of additional macroeconomic risks, including real output and inflation shocks, are significantly priced in the cross-section. A Bayes factor analysis massively favors of the proposed change-point model.

We characterize the consistency of a large class of nonexpected utility preferences (including mean-variance preferences and prospect theory preferences) with stochastic orders (for example, stochastic dominances of different degrees). Our characterization rests on a novel decision theoretic result that provides a behavioral interpretation of the set of all derivatives of the functional representing the decision maker's preferences. As an illustration, we consider in some detail prospect theory and choice-acclimating preferences, two popular models of reference dependence under risk, and we show the incompatibility of loss aversion with prudence.

The hot hand fallacy refers to a belief in the atypical clustering of successes in sequential outcomes when there is none. It has long been considered a massive and widespread cognitive illusion with important implications in economics and finance. The strongest evidence in support of the fallacy remains that from the canonical domain of basketball, where the widespread belief in the existence of hot hand shooting, among expert players and coaches, has been found to have no evidential basis (Gilovich, Vallone, and Tversky 1985). A prominent exhibit of the fallacy is Koehler and Conley (2003)'s study of the NBA Three-Point Contest (1994-1997), a setting which is viewed as ideal for a test of the hot hand (Thaler and Sunstein 2008). In this setting, despite the well-known beliefs of players, coaches, and fans alike, Koehler and Conley find no evidence of hot hand shooting. In the present study, we collect 29 years of shooting data from television broadcasts of the NBA Three-Point Contest (1986-2015), and apply a statistical approach developed in Miller and Sanjurjo (2014), which is more powered, contains an improved set of statistical measures, and corrects for a substantial downward bias in previous estimates of the hot hand effect. In contrast with previous studies, but consistent with Miller and Sanjurjo (2014)'s recent finding of substantial hot hand shooting in all previous controlled shooting studies (including that from the original study of Gilovich, Vallone, and Tversky), we find substantial evidence of hot hand shooting in the NBA Three-Point Contest. This leaves little doubt that the hot hand not only exists, but actually occurs regularly. Thus, belief in the hot hand, in principle, is not a fallacy.

Exploiting the timing of the 2005-2006 Italian bankruptcy law reforms, we disentangle the effects of reorganization and liquidation in bankruptcy on bank financing nd firm investment. A 2005 reform introduces reorganization procedures facilitating loan renegotiation. The 2006 reform subsequently strengthens creditor rights in liquidation. The first reform increases interest rates and reduces investment. The second reform reduces interest rates and spurs investment. Our results highlight the importance of identifying the distinct effects of liquidation and reorganization, as these procedures differently address the tension in bankruptcy law between the continuation of viable businesses and the preservation of repayment incentives.

Severe economic downturns, characterized by deleverage, are typically preceeded by phenomena of debt overhang. This evidence suggests that large recessions may not be the result of large shocks, but, rather, of the interaction between typical shocks and the current state of the economy. We study the transmission of deleverage shocks in a stochastic economy with heterogeneous agents and occasionally binding collateral constraints, where debt evolves endogenously. Our key finding is that the impact effect of a deleverage shock on aggregate output is a non-linear, S-shaped, function of the accumulated level of debt. At low levels of debt, deleverage is almost neutral, whereas its negative impact is largely magnified when debt reaches a critical threshold, i.e., when financial fragility is sufficiently high. At this threshold, the constraint on borrowing becomes endogenously binding. However, when the level of debt is already high before the shock hits, the borrowers are constrained both ex-ante and ex-post. In this case, the effect on output of a deleverage shock is the highest, but, at the margin, roughly insensitive to the level of debt. This non-linearity is much more pronounced for deleverage shocks than for productivity shocks. Our results cast doubts on the accuracy of gauging the effects of financial disturbances in linearized, certainty-equivalence environments.

We study the patterns of political selection in majoritarian versus proportional systems. Political parties face a trade-off in choosing the mix of high and low quality candidates: high quality candidates are valuable to the voters, and thus help to win the elections, but they crowd out the parties' most preferred loyal candidates. In majoritarian elections, the share of high quality politicians depends on the distribution of competitive versus safe (single-member) districts. Under proportional representation, politicians' selection depends on the share of swing voters in the entire electorate. We show that, as the share of competitive districts increases, the majoritarian system begins to dominate the proportional system in selecting high quality politicians. However, when the share of competitive districts becomes large enough, a non-linearity arises: the marginal (positive) effect of adding high quality politicians on the probability of winning the election is reduced, and proportional systems dominate even highly competitive majoritarian.

We consider real pre-Hilbert modules H on Archimedean f-algebras A with unit e. We provide conditions on A and H such that a Riesz representation theorem for bounded/continuous A-linear operators holds.

Does welfare improve when …firms are better informed about the state of the economy and can better coordinate their decisions? We address this question in an elementary business-cycle model that highlights how the dispersion of information can be the source of both nominal and real rigidity. Within this context we develop a taxonomy for how the social value of information depends on the two rigidities, on the sources of the business cycle, and on the conduct of monetary policy.