[R] multinom function

[alexbri]

Dear all:

 

I am trying to fit a multinomial log linear model to the following data:

 

worms<- data.frame(year= rep(2000:2004, c(3,3,3,3,3)),age=rep(1:3,5), mud=c(2,5,0,8,7,7,5,9,14,12,8,7,5,13,11),sand=c(4,7,13,4,14,13,20,17,15,23,20,9,35,27,18), rocks=c(2,6,7,9,3,2,2,10,5,19,13,17,11,20,29))

 

mud, sand and rocks are the 3 factors while age and year are predictors.

Can I fit a model with the multinom function (nnet library) to the data in this form?

 

k<- as.matrix(worms[,3:5])

m1<- multinom(k~year+age,data=worms)

 

Is this correct, or is there another way?

 

Thanks for your help, best wishes

 

Alex