Displaying 1 result from an estimated 1 matches for "grouped_hpi".
2011 Sep 01
3
betareg question - keeping the mean fixed?
...dataset with proportions that vary around a fixed mean, is it
possible to use betareg to look at variance in the dispersion parameter
while keeping the mean fixed?
I am very new to R but have tried the following:
svec<-c(qlogis(mean(data1$scaled)),0,0,0)
f<-betareg(scaled~-1 | expt_label + grouped_hpi, data=data1, link.phi="log",
control=betareg.control(start=svec))
I understood that y~-1 could be used to give a fixed mean of 0.5 however I
get the following error:
Error in linkinv(x %*% beta + offset) :
Argument eta must be a nonempty numeric vector
I think I can work round t...