We estimate trends in diversification for equity, debt, and real estate within and across countries. After 2000, we uncover a marked and near ubiquitous decline in diversification, which coincides with sharply higher levels of investment risk. This decline is associated with country economic...

In this paper, the impact of investment horizon on asset co-skewness is examined both empirically and theoretically. We detail a strong horizon-based estimation bias for co-skewness. An asset that has positive co-skewness in one horizon may have negative co-skewness in another. This phenomenon...

We estimate a discrete approximation of the risk-return trade-off for the US market by using the whole universe of stocks from July 1963 to September 2017. We find the relationship between return and risk to be time-varying and also dependent on the level of risk considered. The proposed...

We examine machine learning and factor-based portfolio optimization. We find that factors based on autoencoder neural networks exhibit a weaker relationship with commonly used characteristic-sorted portfolios than popular dimensionality reduction techniques. Machine learning methods also lead to...

We define and measure integration among a sample of 357 US banks over 25 years from 1993 to 2017 and show that the median US bank's integration has increased significantly post-2005. During the great recession and the Eurozone crisis, integration levels among US banks display a significant rise...