I want to test for panel unit root using "pCARDtest" but it returns: function cannot be found. I want help on this.
I tried the CIPS test for panel unit root too. But it also returned an error(attached below).
cipstest(CCA, type = "drift")
Error in approx(nintv, cvals[nintl:ninth, tintl, i], n = max(nintv) - :
need at least two non-NA values to interpolate