Hey Stata users,
I am having a problem using the Hausman test of independence of irrelevant alternatives (IIA) following the estimation of a multinomial logistic regression model. I have a three category nominal dependent variable called DV (0 = no college, 1 = immediate enrollment in college, and 2 = on-time enrollment in college).
I first estimate the model:
mlogit DV x1 x2 x3 x4
STATA estimates the model with no problem. I then use the commands to obtain the Hausman test:
mlogtest, hausman base
STATA tells me
**** Hausman tests of IIA assumption
Ho: Odds(Outcome-J vs Outcome-K) are independent of other alternatives.
no coefficients in common; specify -equations(matchlist)- for the problem of different equation names. r(498);
Does anyone know if I am doing something wrong?
Thanks in advance for your help,
Robert
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