data <- matrix(scan(),ncol=2,byrow=TRUE)
 1 1  2 1  3 1
 5 2  3 2  4 2
 6 3  7 3  5 3

data
KWexample1 <- data.frame(data)
colnames(KWexample1) <- c("y","group")
KWexample1$group <- as.factor(KWexample1$group)    # to make sure that group is a factor, not numeric

rm(data)
KWexample1

boxplot(y ~ group, data=KWexample1,main="Hypothetical data")

anova(lm(y ~ group, data=KWexample1))             # standard ANOVA

kruskal.test(y ~ group, data=KWexample1)          # Kruskal-Wallis test




data <- matrix(scan(),ncol=2,byrow=TRUE)          # try again with an outlier
 1 1  2 1  3 1
 5 2  3 2  4 2
 6 3  27 3  5 3

data
KWexample2 <- data.frame(data)
colnames(KWexample2) <- c("y","group")
KWexample2$group <- as.factor(KWexample2$group)    # to make sure that group is a factor, not numeric
rm(data)
KWexample2


boxplot(y ~ group, data=KWexample2,main="Hypothetical data with outlier")

anova(lm(y ~ group, data=KWexample2))             # standard ANOVA

kruskal.test(y ~ group, data=KWexample2)          # Kruskal-Wallis test



rm(KWexample1,KWexample2)                  # remove objects when finished