Re: st: Conditional logit - Coefficient of the base variable?

[Maarten Buis <maartenlbuis@gmail.com>]

On Tue, Mar 13, 2012 at 3:38 PM, Hadji Cortez Jalotjot wrote:
> I estimated a conditional logit model for vehicle choice from a the data I got in a discrete choice experiment.  In the model, explanatory variables for choice is the vehicle attributes itself (i.e. engine type, price, range, emission level, presence of incentive, etc).  Each vehicle attribute has several levels (e.g. engine - gas, diesel, lpg.......).  I set one level for each attribute as the base variable and got the results.
>
> Now, I want to use this model to estimate possible effects of policies on vehicle choice.  I will use sample enumeration method but I'm afraid I need the coefficients for the base variable.  Is it possible to compute this based on the results?

For a set of indicator variables the coefficient for the baseline
category is easily computed, it is 0. However I guess you are looking
for something more in the line of this Stata tip that is about to
appear in the next issue of the Stata Journal:

M.L. Buis (forthcoming) "Stata tip 106: With or without reference",
The Stata Journal, 12(1).
<http://www.maartenbuis.nl/publications/ref_cat.html>

Hope this helps,
Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany


http://www.maartenbuis.nl
--------------------------

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