##generate some data:
set.seed(123) #for reproducibility
y <- rnorm(30) #generate Y
x <- matrix(rnorm(30*10), 30, 10) #create matrix of Xs
##typical situation:
mymodel <- lm(y ~ x)
as.arx(mymodel)
##use hetero-robust vcov:
as.arx(mymodel, vcov.type="white")
##add ar-dynamics:
as.arx(mymodel, ar=1:2)
##add log-variance specification:
as.arx(mymodel, arch=1:2)
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