We relate time-varying aggregate ambiguity (V-VSTOXX) to individual investor trading. We use the trading records of more than 100,000 individual investors from a large German online brokerage from March 2010 to December 2015. We find that an increase in ambiguity is associated with increased...

This paper studies optimal equity portfolios with long-term horizon under heterogeneous risk aversion levels. We focus on European stocks and empirically show that contemporaneous excess returns of semi-active strategies are negatively associated with market conditions and sentiment. Consistent...

This paper develops a tractable dynamic model of competition between two risk-averse portfolio managers who attempt to outperform each other by trading in different stocks, reflecting asset specialization. We characterize explicitly the unique Nash equilibrium portfolio policies, and show that a...

We employ two reward and risk measures, the Upper Partial Moment and the Lower Partial Moment, in order to maximize different value functions under the budget and the short-selling constraints. We find that agents seem to prefer small capitalization and high value stock portfolios (which are...

We consider an investor who faces parameter uncertainty in a continuous-time financial market. We model the investor's preference by a power utility function leading to constant relative risk aversion. We show that the loss in expected utility is large when using a simple plug-in strategy for...

I investigate a dynamic life-cycle strategic asset allocation and consumption problem under model uncertainty, where both inflation rate and income growth rate are assumed to be estimated with errors. I present a feasible boundary for the uncertainty aversion parameter, which measures the...

I investigate a dynamic life-cycle strategic asset allocation and consumption problem under model uncertainty, where both inflation rate and income growth rate are assumed to be estimated with errors. I present a feasible boundary for the uncertainty aversion parameter, which measures the...

Compared with extensive empirical literature on contrarian strategy, we build a dynamic mean-variance model with geometric mean reversion stock price which implies a contrarian strategy. Our model suggests that the investor should buy distressed stocks, and sell them after the company recovers....

We theoretically show that there is a fundamental disconnect between the disposition effect, i.e., investors’ tendency to sell winning assets too early and losing assets too late, and its common empirical measure, namely a positive difference between the proportion of gains and losses...

We theoretically show that there is a fundamental disconnect be- tween the disposition effect, i.e., investors’ tendency to sell winning assets too early and losing assets too late, and its common empirical measure, namely a positive difference between the proportion of gains and losses re-...