# NOT RUN {
library(nlme)
data(Oxide)
vcf = varComp(Thickness~Source, Oxide, ~Lot/Wafer)
coef(vcf, 'varComp')
p.value(varComp.test(vcf)) ## test both Lot and Wafer%in%Lot
p.value(varComp.test(vcf, null=1)) ## test Wafer%in%Lot
# }
Run the code above in your browser using DataLab