Contrary to the classic framework of passive strategies, if investors exploit return predictability through active strategies then there is a tension between the mean-variance frontiers that drive empirical work and the mean-variance preferences that are used in finance theory. We show that...

This paper studies asset markets in which ambiguity averse investors face Knightian uncertainty about expected payoffs. The same investors, however, might wish to resolve their uncertainty, although not risk, by just purchasing information. In these markets, uninformed and, hence, ambiguity...

We show that the level of interest rates determines the magnitude of mispricing at the turn of the tax year, as investors face the trade-off between selling a temporarily-depressed stock this year and selling next year, but delaying tax implications by one year. Interest rates do explain the...

We use asset pricing insights to study importance of micro-level frictions for aggregate quantities. In our model, the relevant stochastic variable is a stationary growth rate (necessary to produce high Sharpe Ratios in a Long Run Risk world), as opposed to a trend-stationary level of...

We study a model where a capital provider learns from the price of a firm’s security in deciding how much capital to provide for new investment. This feedback effect from the financial market to the investment decision gives rise to trading frenzies, where speculators all wish to trade like...