that is a Steven Kopits commented.
figure 1: M2 in billions, seasonally adjusted, logarithmic scale (blue). Source: Federal Reserve via FRED.
- Use ADF to reject 10% root of unit nulls (intercept): no,
- Use ADF to reject unit root nulls at 10% (intercept, trend): no
- Use DF-Elliott-Rothenberg-Stock to reject 10% root of unit nulls (intercept): No
- Reject unit root nulls at 10% using DF-Elliot-Rothenberg-Stock (intercept, trend): no
- Reject 1% mean stationary nulls using KPSS: Yes
- Reject 1% trend stationary nulls using KPSS: Yes
If there is such a debate, I miss the conclusion (and the general consensus in economics) that Mr. Kopitts is referring to.
Perhaps he was referring to the velocity (M2):
figure 2: The speed of the M2. Sources: Federal Reserve, BEA via FRED, and authors’ calculations.
- Use ADF to reject 10% root of unit nulls (intercept): no,
- Use ADF to reject unit root nulls at 10% (intercept, trend): no
- Use DF-Elliott-Rothenberg-Stock to reject 10% root of unit nulls (intercept): No
- Reject unit root nulls at 10% using DF-Elliot-Rothenberg-Stock (intercept, trend): no
- Reject 1% mean stationary nulls using KPSS: Yes
- Reject 1% trend stationary nulls using KPSS: Yes