Long‐run predictability tests are even worse than you thought
长期预测能力检验比你想象的更糟
Summary We derive asymptotic results for the long‐horizon ordinary least squares (OLS) estimator and corresponding ‐statistic for stationary autoregressive predictors. The ‐statistic—formed using the correct asymptotic variance—together with standard‐normal critical values result in a correctly‐sized test for exogenous predictors. For endogenous predictors, the test is size distorted regardless of the persistence in the predictor and adjusted critical values are necessary.…