Hi members,

Got a quick question about linear combination of coefficients (using lincom command).
I am interested in a policy (binary var.)'s influence on Y (continuous dependent var.) depending on GDP (logged GDP per capita).
When I run a model, the policy var. doesn't have statistical significance, but the interaction with GDP has.

To see, if any, in what range of GDP, the policy var. has significance, I ran multiple sets of lincom with diffferent GDP values with certain interval covering all GDP value ranges.
And all of the lincom result has positive significant coefficient.

I have hard time interpreting this because if the policy has positive effect on all levels of GDP, shouldn't the variable have positive significant effect in the model before postestimations?
I wonder if somebody could put his/her opinion on this.

Thanks!

Best,
Gru