“…The most popular unit root test is the classical augmented-Dickey Fuller (ADF) test Fuller 1979, 1981). Implementations of the ADF test are incorporated in various packages, in particular CADFtest (Lupi 2009), fUnitRoots (Wuertz, Setz, and Chalabi 2017), tseries (Trapletti, Hornik, and LeBaron 2019), and urca (Pfaff 2008). 1 As we will argue in the next section, most 'standard' unit root tests, such as the ones implemented in these packages, require seemingly innocuous choices from the practitioner regarding model specifications or which test to use, that may have a major impact on the performance of the unit root tests.…”