We build a simple diagnostic criterion for approximate factor structure in large panel datasets. Given observable factors, the criterion checks whether the errors are weakly cross-sectionally correlated or share at least one unobservable common factor (interactive effects). A general version...

This paper develops and presents the prior adaptive group lasso for generalized linear models. The prior adaptive group lasso is an extension of the prior lasso developed by Jiang, He, and Zhang (2016), which allows for the use of existing information from previous or similar studies in the...

We develop a penalized two-pass regression with time-varying factor loadings. The penalization in the first pass enforces sparsity for the time-variation drivers while also maintaining compatibility with the no arbitrage restrictions by regularizing appropriate groups of coefficients. The second...

Using filtering techniques, spectral analysis, and Markov chain models, I document trends and cycles of factors have significantly changed over the period to December 2000 compared to the period post-January 2001. The recent weaker performance of value in the 21st century, including the value...

We explore the cost of implicit leverage associated with an S&P 500 Index futures contract and derive an implied financing rate (the Futures-Implied Rate or FIR), based on a simple model of stock and futures, without any explicit arbitrage or other relationship to market interest rates. We...

Order book and transactions data from the U.S. Treasury securities market are used to calculate daily measures of bid-ask spreads, depth, and price impact for a twenty-six-year sample period (1991-2017). From these measures, a daily index of Treasury market liquidity is constructed, reflecting...

This paper uncovers and explains the emergence of cycles of intraday declines and overnight reversals in the U.S. stock market in the 21st century. Using quote midpoints for the past 24 years of common stocks traded in the three main exchanges, I show that the cross-sectional association between...