xtabond2 suppressing the constant

Hi all,

When using the difference GMM estimator, the constant is differenced out by way of the first-difference transformation. So using the option "noconstant" is moot.

But what is the interpretation of the constant in System GMM? The system GMM uses the original levels equation and the first differenced equation to create a "system" of equations allowing for more instruments and usually greater efficiency. So is the constant term coming from the levels equation in System GMM?? :confused:

Thank you in advance