bab3 hal104

#################################
## Uji t dua sampel independen ##
#################################

subset.InsectSpray = InsectSprays[InsectSprays$spray%in%c("A","C"),]

attach(subset.InsectSpray)
#tes kenormalan
#for variable count
shapiro.test(count)

#test for equal variance
var.test(count~spray)

subset.InsectSpray$spray=factor(subset.InsectSpray$spray, levels=c("A","C"))
boxplot(count~spray,data=subset.InsectSpray,xlab="type of spray",ylab="insect count",main="inspectsprays data", varwidth=TRUE, col="lightgray")