Hi!

I've been trying to write an MLE script for a Probit model where the dependent value can take 3 values, but when I run the script, I get an "Data types not conformable for operation". What does that mean and how do I fix it?

mle loglik3 = (yy=1)ln(cnorm(c1-xb2)) + (yy=2)ln(cnorm(c2-xb2) - cnorm(c1-xb2)) + (yy=3)ln(1 - cnorm(c2-xb2))
    scalar c1 = -10
    scalar c2 = -10
    scalar pb1 = -10
    scalar pb2 = -10
    series xb2 = pb1*x1 + pb2*x2
    params pb1 pb2 c1 c2
end mle

gretl version 1.8.4
Current session: 2010-02-25 16:24
? mle loglik3 = (yy=1)ln(cnorm(c1-xb2)) + (yy=2)ln(cnorm(c2-xb2) - \
cnorm(c1-xb2)) + (yy=3)ln(1 - cnorm(c2-xb2))
? scalar c1 = -10
? scalar c2 = -10
? scalar pb1 = -10
? scalar pb2 = -10
? series xb2 = pb1*x1 + pb2*x2
? params pb1 pb2 c1 c2
? end mle
Data types not conformable for operation

Error executing script: halting
> end mle