Understanding correlations in complex systems is crucial in the face of turbulence, such as the ongoing financial crisis. However, in complex systems, such as financial systems, correlations are not constant but instead vary in time. Here we address the question of quantifying state-dependent...

It is widely agreed that the Nasdaq during the dot-com era 20 years ago was a full-fledged stock market bubble. Recently, the US stock market according to many metrics has become significantly more speculative and overvalued than it was at the dot-com peak 20 years ago. In both instances, a very...

The paper studies the constrained efficiency of the aggregate stock market in which the investor obtains gain-loss utility directly from fluctuations in asset returns, in addition to consumption. I reveal that the competitive equilibrium is inefficient without any frictions as long as the agent...

This paper specifies and estimates a structural dynamic stochastic model of the way individuals make retirement and saving choices in an uncertain world, and applies that model to analyze the effects of the stock market bubble on retirement behavior. The model includes individual variation both...

Stock market anomalies representing the predictability of cross-sectional stock returns are one of most controversial topics in financial economic research. This chapter reviews several well-documented and pervasive anomalies in the literature, including investment-related anomalies, value...

Investigating linkages between credit and equity markets, we consider daily aggregate U.S. CDS spreads as well as well-chosen equity market and implied volatility indexes over ten years. We describe such robust (to spurious correlation) relationship with the quantile cointegrating regression...

Human judgments are systematically affected by various biases and distortions. The main goal of our study is to analyze the effects of five well-documented behavioral biases — namely, the disposition effect, herd behavior, availability heuristic, gambler's fallacy and hot hand fallacy — on...

This paper provides evidence that a firm's stock price movements affect its customer demand. I develop a model in which customers learn about a firm's product quality partially from its stock price. This learning induces feedback from the price to customer demand. Furthermore, the firm manager...

We study the dynamics of a Lucas-tree model with finitely lived agents who 'learn from experience.' Individuals update expectations by Bayesian learning based on observations from their own lifetimes. In this model, the stock price exhibits stochastic boom-and-bust fluctuations around the...

We study the dynamics of a Lucas-tree model with finitely lived agents who "learn from experience." Individuals update expectations by Bayesian learning based on observations from their own lifetimes. In this model, the stock price exhibits stochastic boom-and-bust fluctuations around the...