Displaying 1 result from an estimated 1 matches for "crudemat".
2007 Nov 13
1
FW: Reference category for explanatory factors
...ms of what I have done
but will explain nonetheless.
I am using the msm.package and trying to specify my reference category
for an outcome covariate. The following command line works:
## age of respondent - using year5a: categorical
preg_fyear5a.msm<-msm(outcome~ipi, subject=id, data, qmatrix=crudemat,
exacttimes=TRUE, covariates=~factor(year5a))
However, in the dataset (data) the reference category 0 is a moderately
small cell, so I would like to change it to 1 which is much large.
There are 5 categories in the covariates year5a (0,1,2,3,4).
I have tried all sorts of approaches with 'orde...