Cross-Market Alpha: Testing Short-Term Trading Factors in the U.S. Market via Double-Selection LASSO
We test whether 168 short-horizon price-volume signals from the Alpha191 library, originally developed for China's retail-dominated A-share market, contain pricing information for S&P 500 stocks from 2002 to 2022 beyond 153 established U.S. factors. Using the double-selection LASSO of Feng et al. (2020), 17 signals receive significant stochastic discount factor (SDF) loadings in the baseline test-asset design. Their robustness is uneven. Only three signals (a multi-horizon moving-average ratio, a directional-pressure ratio, and a price-gap correlation) remain significant with a finer test-asset grid and under Elastic Net and principal-component control selection; six more pass most checks, and the remaining eight depend on the specification. Robust signals are concentrated in volume-price interaction and short-term mean reversion, whereas volatility-based signals are fragile.