Skip to content
# Start coding here...

library(readr)
Menu <- c(rep("Menu 1",6),rep("Menu 2",6),rep("Menu 3",6))
Sales <- c(22,42,44,52,45,37,52,33,8,47,43,32,16,24,19,18,34,39)
data2 <- data.frame(Menu, Sales)
data2
#Convert treatment into factor
Treatment = as.factor(data2$Menu)
Treatment
results <- lm(Sales ~ Menu, data2)
anova(results)
Treatment = as.factor(data2$Menu)
results = aov(Sales~Treatment,data2)
summary(results)

Model Checking

#find residual
residuals <- resid(results)
residuals
#Predicted
predicted= predict(results)
predicted
library(ggpubr)
ggqqplot(residuals)
#Shapiro
shapiro.test(residuals)
library(car)
durbinWatsonTest(residuals)