[R] nnet multinom question

[Moritaka Hosotsubo]

I'd like to fit a multinomial log-linear model for 4 categories of the form:

 log[(P(D=i | x)/P(D=0 | x)] = alpha + beta_i x for i = 1,2,3.

Is there a way to impose such a constraint in the multinom function of nnet
or another function of some library?

regards,

Hosotsubo

--
Moritaka Hosotsubo

National Institute for Science and Technology Policy, MEXT, Japan.

East Bulidg.16F, Central Government Building No.7,
3-2-2 Kasumigaseki, Chiyoda-ku, Tokyo, 100-0013
E-mail: hosotubo ¡÷ nistep.go.jp
FAX: +81-3-3503-3996