Hello,

I am having a panel model where it says that :


ΔY= (1-a) + b1yI,t-1 + b2ytI,-1 + Zi,t + Di,t + e,it,



Where Y is the dependent variable of interest, Z a set of control variables, and D a set of dummy variables.

What is not clear to me is how to create the 1-a term of the equation. In other words, how to subtract the constant term from the unit,

Any help is appreciated

Best.
Marip Ferri!