x1=rnorm(20)
x2=rnorm(20)
x3=2*x1
x4=rnorm(20)
x5=3*x4
y=0.18*x1-2.23*x2+1.22*x3+2.62*x4-1.79*x5
data.frame(x1,x2,x3,x4,x5)
a=data.frame(x1,x2,x3,x4,x5)
cor(a)
library(car)
attach(a)
fm=lm(y~.,data=a)
到vif这一步会显示:
vif(fm)
Error in vif.default(fm) : there are aliased coefficients in the model
r软件刚入门,求问这是什么原因?怎么解决?