Covariance matrix estimation and principal component analysis (PCA) are two cornerstones of multivariate analysis. Classic textbook solutions perform poorly when the dimension of the data is of a magnitude similar to the sample size, or even larger. In such settings, there is a common remedy for both statistical problems: nonlinear shrinkage of the eigenvalues of the sample covariance matrix. The optimal nonlinear shrinkage formula depends on unknown population quantities and is thus not available. It is, however, possible to consistently estimate an oracle nonlinear shrinkage, which is motivated on asymptotic grounds. A key tool to this end is consistent estimation of the set of eigenvalues of the population covariance matrix (also known as the spectrum), an interesting and challenging problem in its own right. Extensive Monte Carlo simulations demonstrate that our methods have desirable finite-sample properties and outperform previous proposals.
We analyze intergenerational redistribution in emerging economies with the aid of an overlapping generations model with endogenous labor supply. Growth is initially high but declines over time. A version of the model calibrated to China is used to analyze the welfare effects of alternative pension reforms. Although a reform of the current system is necessary to achieve financial sustainability, delaying its implementation implies large welfare gains for the (poorer) current generations, imposing only small costs on (richer) future generations. In contrast, a fully funded reform harms current generations, with small gains to future generations.
A key ingredient of many popular asset pricing models is that investors exhibit countercyclical risk aversion, which helps explain major economic puzzles such as the strong and systematic variation in risk premiums over time and the high volatility of asset prices. There is, however, surprisingly little evidence for this assumption because it is difficult to control for the host of factors that change simultaneously during financial booms and busts. We circumvent these control problems by priming financial professionals with either a boom or a bust scenario and by subsequently measuring their risk aversion in two experimental investment tasks with real monetary stakes. Subjects who were primed with a financial bust were substantially more risk averse than those who were primed with a boom. Subjects were also more fearful in the bust than in the boom condition, and their fear is negatively related to investments in the risky asset, suggesting that fear may play an important role in countercyclical risk aversion. The mechanism described in this paper is relevant for theory and has important implications, as it provides the basis for a self- reinforcing process that amplifies market dynamics.
This article examines the effects of market structure on the variety of research projects undertaken and the amount of duplication of research. A characterization of the equilibrium market portfolio of R&D projects and the socially optimal portfolio is provided. It is shown that a merger decreases the variety of developed projects and decreases the amount of duplication of research. An increase in the intensity of competition among firms leads to an increase in the variety of developed projects and a decrease in the amount of duplication of research.
This paper explores how extended unemployment insurance (UI) benefits targeted to older workers affect early retirement and social welfare. The trade-off of optimal UI between consumption smoothing and moral hazard requires accounting for the entire early retirement system, which often includes extended UI and relaxed access to disability insurance (DI). We argue that extended UI generates program complementarity (increased take-up of UI followed by DI and/or regular retirement benefits) and program substitution (increased take-up of UI instead of DI). Exploiting Austria's regional extended benefit program, which extended regular UI benefits to up to 4 years, we find: (i) program complementarity is quantitatively important for workers aged 50+; and (ii) program substitution is quantitatively relevant for workers aged 55+. We derive a simple rule for optimal UI that accounts for program complementarity and program substitution. Using the sufficient statistics approach, we conclude that UI for older workers was too generous and the regional extended benefit program was a suboptimal policy.
We derive a necessary and sufficient condition for the existence of equilibria with only two active players in the all-pay auction with complete information and identity-dependent externalities. This condition shows that the generic equilibrium of the standard all-pay auction is robust to the introduction of "small" identity-dependent externalities. In general, however, the presence of identity-dependent externalities invalidates well-established qualitative results concerning the set of equilibria of the first-price all-pay auction with complete information. With identity-dependent externalities equilibria are generally not payoff equivalent, and identical players may earn different payoffs in equilibrium. These observations show that Siegel’s (2009) results characterizing the set of equilibrium payoffs in all-pay contests, including the all-pay auction as a special case, do not extend to environments with identity-dependent externalities. We further compare the all-pay auction with identity-dependent externalities to the first-price winner-pay auction with identity-dependent externalities. We demonstrate that the equilibrium payoffs of the all-pay auction and winner-pay auction cannot be ranked unambiguously in the presence of identity-dependent externalities by providing examples of environments where equilibrium payoffs in the all-pay auction dominate those in the winner-pay auction and vice versa.
This paper analyzes whether hosting the most prestigious European cultural event, the European Capital of Culture, has an impact on regional economic development or the life satisfaction of the local population. Concerning the economic impact, we show that European Capitals are hosted in regions with above average GDP per capita, but do not causally affect the economic development in a significant way. Even a positive impact on GDP per capita would not imply a positive impact on individual utility or social welfare of the regional population. Surprisingly, using difference-in-difference estimations, a negative effect on the well-being of the regional population is found during the event. Since no effect is found before the event, reverse causality and positive anticipation can be ruled out. The negative effect during the event might result from dissatisfaction with the high levels of public expenditure, transport disruptions, general overcrowding or an increase in housing prices.
We assess the role of financial linkages in the transmission of sovereign risk in the Euro Crisis. Building on the narrative approach by Romer and Romer (1989), we use
financial news to identify structural shocks in a vector autoregressive model of daily sovereign CDS premia for eleven European countries. To estimate how these shocks
transmit across borders, we use data on cross-country bank exposures to sovereign debt. Our results indicate that exposure to Greek sovereign debt and the debt of
Greek banks constitute important transmission channels. All else being equal, the transmission rate to the country with the greatest exposure to Greece (1.22 percent of GDP) has been roughly 46 percent higher than the rate to the country with the least exposure (0.08 percent of GDP).
This paper investigates empirically how similarity of demand structures - approximated by similarity of income distributions - affects trade patterns along both the extensive and intensive margin. The idea that similarity of demand structures intensifies trade goes back to the well-known Linder hypothesis. Based on a sample of 102 countries, I find that bilateral trade volumes are increasing in the overlap of two countries income distributions. This effect is driven by both the extensive and intensive margin. I establish two novel measures of income similarity - the average income level of the overlap area and the range of incomes for which two distributions overlap - and document that both are important determinants of bilateral trade margins. My analysis shows that the positive relationship between similarity of income distributions and bilateral trade margins is present at the aggregate and disaggregate level of trade flows.
