Recent studies find that idiosyncratic risk (IR) has increased since the 1960's and attribute this to economy wide factors such as the role of the IT revolution. To gain further insights into why IR has increased over time, our paper uses industry level data and firm level data to study if...

Focusing on capital asset returns governed by a factor structure, the Arbitrage Pricing Theory (APT) is a one-period model, in which preclusion of arbitrage over static portfolios of these assets leads to a linear relation between the expected return and its covariance with the factors. The APT,...

In this paper we propose exact likelihood-based mean-variance efficiency tests of the market portfolio in the context of Capital Asset Pricing Model (CAPM), allowing for a wide class of error distributions which include normality as a special case. These tests are developed in the framework of...

In this paper, I obtain new measures of the value of active portfolio management by forming replicating portfolios. These measures allow for a separate evaluation of fund managers' strategic and tactical decisions. I also obtain new evidence on the value of trading by decomposing it into...

This paper investigates the effects of the issuance of retail products with non-linear payoffs on option prices. For a given underlying asset, when the outstanding volume of products embedding a short-put position increases, implied volatility at the corresponding strike decreases. A similar...

This study investigates the impact of uncertainty on the mean-variance relationship. We find that the stock market’s expected excess return is positively related to the market’s conditional variances and implied variance during low uncertainty periods but unrelated or negatively related to...

This paper examines the main drawbacks of technical analysis. Although this is widely used by practitioners, from an academic perspective it can only be seen as a form of "voodoo finance". In particular, it runs into the following pitfalls: Subjectivity; Doubtful assumptions; Unjustified...

This working paper was written by Patrick Augustin (McGill University and Canadian Derivatives Institute), Mikhail Chernov (University of California Los Angeles, NBER and CEPR), Lukas Schmid (University of Southern California and CEPR) and Dongho Song (Johns Hopkins University).We show...

Using administrative data on deposits and loans of every Norwegian with every Norwegian bank, we show that an existing deposit account makes a household more likely to hold deposits at the same bank later despite better alternatives and more likely to borrow there. Consistent with this, banks...

We propose that investment strategies should be evaluated based on their net-of-trading-cost return for each level of risk, which we term the "implementable efficient frontier." While numerous studies use machine learning return forecasts to generate portfolios, their agnosticism toward trading...