hardness: Hardness and a Block Experiment
In ACSWR: A Companion Package for the Book "A Course in Statistics with R"

Description Usage Format References Examples

Four types of tip are used which form the blocks in this experiment. The variable of interest is the hardness which further depends on the type of metal coupon. For each type of the tip, the hardness is observed for 4 different types the metal coupon.

1	data(hardness)

A data frame with 16 observations on the following 3 variables.

Tip_Type: Four types of tip which form the blocks
Test_Coupon: Four different types of metal coupons
Hardness: Hardness of the coupon

Montgomery, D. C. (1976-2012). Design and Analysis of Experiments, 8e. J.Wiley.

data(hardness)
hardness$Tip_Type <- as.factor(hardness$Tip_Type)
hardness$Test_Coupon <- as.factor(hardness$Test_Coupon)
hardness_aov <- aov(Hardness~Tip_Type+Test_Coupon,data=hardness)
summary(hardness_aov)