[R] System exactly singular with pgmm (package plm)

his is my first post, I'll do my best to be clear and complete. I am trying to run a pgmm regression (Arellano Bond estimator) following the example online with the EmplUK dataset. My dataset is unbalanced, with some missing values (that I also removed, without any difference). This is the paste

[R] Problem with package plm

Hi! I am trying yo run a regression using the plm package. I tried in two different ways, that should give the same result, but eventually do not; and i cannot understand the reason. - The first way: Accellerator.model - read.delim(~/Desktop/Tesi/Accellerator model.txt) data - Accellerator.model