This paper focuses on testing non-stationary real-time data for forecastability, i.e., whether data revisions reduce noise or are news, by putting data releases in vector-error correction forms. To deal with historical revisions which affect the whole vintage of time series due to redefinitions,...

This study provides a critical assessment of long-horizon return predictability tests using highly persistent regressors. We show that the most commonly used test statistics are typically oversized, leading to spurious inference. As a remedy, we propose a simple Wald statistic, which can...