[Limdep Nlogit List] inclusive value contraint

[Kandice L. Kleiber]

Hi -
I am estimating a nested logit model using sequential estimation.
Tree = [cnsb(corn, soybean), wheat, other]

I estimate the lower level and get the inclusive values.  When I estimate
the upper level, I only want the inclusive values to be included in the cnsb
option, thus the parameter on the inclusive value for wheat and other should
equal zero.

My coding is as follows (assuming I already have estimated the lower level
and gotten the inclusive values) (I normalize on 'other'):
nlogit;
lhs = ulev;
choices, ucs, uwheat, uother;
rhs = one, edb1, edb2, edc1, edc2, occup1, occup2, age1, age2, agesq1,
agesq2, liv1, liv2, sl051, sl052, ecap1, ecap2, iva0, ivb0$

The values of iva0 and ivb0 are the same, it's just the way the data is set
up.  So I want to include the inclusive value for ucs (ie estimate the
parameter value for the inclusive value) but restrict the parameter value to
zero for the wheat option (because ivb0 does not equal zero, so the
parameter should so it's not included in the utility function).

I have tried to use
ivset: (ivb0)=[0];
but it doesn't recognize it.

Any ideas?

Thank you!
Kandice.

-- 
Kandice L. Kleiber
Graduate Teaching Assistant
Department of Economics
Oregon State University
e: kleiberk at onid.orst.edu
w: 541.737.7717