search for: tcad

...r colleagues, I had a question wrt the car package. How do I evaluate whether a simpler multivariate regression model is adequate? For instance, I do the following: ami <- read.table(file = "http://www.public.iastate.edu/~maitra/stat501/datasets/amitriptyline.dat", col.names=c("TCAD", "drug", "gender", "antidepressant","PR", "dBP", "QRS")) ami$gender <- as.factor(ami$gender) ami$TCAD <- ami$TCAD/1000 ami$drug <- ami$drug/1000 library(car) fit.lm <- lm(cbind(TCAD, drug) ~ gender + antidepressant +...