Bookmark and Share

Notice: On March 31, it was announced that Statalist is moving from an email list to a forum. The old list will shut down on April 23, and its replacement, statalist.org is already up and running.


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

st:A question related to mixlogit package


From   Nina YIN <yinnina.ccer@gmail.com>
To   statalist@hsphsun2.harvard.edu
Subject   st:A question related to mixlogit package
Date   Fri, 1 Jun 2012 10:11:01 +0200

Dear all,

I am currently using comand( mixlogit) to estimate mixed logit model
with individual-level data and have some questions to ask for your
help.

I want to estimate the demand of prescription drug with data of
purchasing records, drug characteristics and individual demographics.

When I use the command,

-mixlogit choice price, group(ncs) id(np) rand(drug characteristics,
individual characteristics, interaction terms)

The results always return with" Variable education has no within-group
variance" or "Variable age has no within-group variance".

In my sample, there have some individual has repeated purchasing,
therefore, as a start, I excluded all the repeated records such that
for each individual there is only one purchasing record. However, it
also returned with this message. I can't get what does it mean. Does
that mean in this type of model, I couldn't include the individual
attribute variables except the interacted terms?

If you ever have had such experience, could you share me with your
opinion? Thanks a lot!


--
Best Regards,
Nina YIN


Toulouse School of Economics
Manufacture des Tabacs
21 Allee de Brienne
Toulouse, 31000, France
Tel: 0033-(0)5 6123 8348
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/


© Copyright 1996–2014 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   Site index