[Limdep Nlogit List] Why estimates remain unaffected when using ordinary weights in rank-ordered logistic regression?

[Valtiala Juho (Luke)]

Dear list members,
I am using rank-ordered logit to analyse the data from a questionnaire in which people were asked to rank their preferences. Farmers are over-represented among the respondents, and I would like to give less weight to farmers' responses. I am using the following NLOGIT command:

DISCRETECHOICE; Lhs=RANK; Choices=1,2,3,4,5; Ranks; Conditional; Rh2=ONE,HIGH_EDUC$

My problem is that when I apply ordinary weights by adding Wts=FWEIGHT argument the results remain unaffected. NLOGIT executes the command normally and the weight variable FWEIGHT is shown in output as expected. So, why the weight has no effect on estimates? Is there a problem with the command or is the problem a theoretic one which I have not considered? The weighting variable has effect when I use ordinary multinomial logit with the preferred alternative instead of ranked alternatives.

Best regards,
Juho Valtiala