Hello,

I'm running PMG model with one dummy veritable of (0 or 1) (xtpmg d.y d.x1 d.x2 d.x3 d.x4 DUM , lr(l.y l.x1 l.x2 l.x3 l.x4 DUM ) ec(ECT) replace pmg),

Unfortun stata show this message (numerical derivatives are approximate flat or discontinuous region encountered)

So, please I do need your help to correct this problem.

Thanks in advance