I
would like to apply a restriction on the coefficients of a linear regression
(OLS). Indeed, coefficients will represent the yield of a crop (soybeans, corn…)
for a specific grade (my data) during its lifecycle.
How
can I apply a restriction on coefficients: I want them to be all positive and
that the first coefficient (grade poor crop) is lower than the second (grade
fair crop), the second coefficient lower than the third (grade good crop)…
Thanks
in advance
French gretl user