NLS estimation problem
Posted: Thu Jun 27, 2013 4:55 am
Hi,
I want to estimate the equation with NLS method:
C_FUEL=C(1)*TC+((1-C(1))*28.6*C(2)-C(1)*38.9*C(3)-C(1)*40.9*C(4))*N
The estimation out put gives me coef. but it does not have prob or t-statistic and it gives me the 'WARNING: Singular covariance - coefficients are not unique'
C(2) and C(3) and C(4) must be positive parameters but i can't add this restriction to equation.
Thank you
aida
I want to estimate the equation with NLS method:
C_FUEL=C(1)*TC+((1-C(1))*28.6*C(2)-C(1)*38.9*C(3)-C(1)*40.9*C(4))*N
The estimation out put gives me coef. but it does not have prob or t-statistic and it gives me the 'WARNING: Singular covariance - coefficients are not unique'
C(2) and C(3) and C(4) must be positive parameters but i can't add this restriction to equation.
Thank you
aida