This data file is intended for use with the Split-Plot Factorial tutorial. A manufacturer wants to determine the effect of three methods of pulp preparation and four levels of cooking temperature on the tensile strength of paper. These twelve combinations can be conducted in one day. To increase statistical power, the paper chemist decides to perform three replicates of this twelve-run general factorial design over three days, which produces a total of 36 runs. However, it is not feasible to perform the experiment in a random fashion. Instead, on each of the three days, this experimenter produces a batch of pulp and divides it into four samples to be cooked at four different temperatures. The process is repeated for pulp prepared by the two other methods. 35 45 35 84 84 84 a2 250 38 a2 275 42 a2 225 41 a2 200 34 a1 250 37 a1 275 36 a1 225 35 a1 200 30 a3 275 36 a3 200 29 a3 225 26 a3 250 33 a2 275 40 a2 225 36 a2 250 42 a2 200 31 a1 225 32 a1 275 41 a1 200 28 a1 250 40 a3 225 30 a3 250 32 a3 200 31 a3 275 40 a1 275 40 a1 250 41 a1 200 31 a1 225 37 a2 275 44 a2 225 40 a2 250 39 a2 200 35 a3 275 45 a3 250 39 a3 200 32 a3 225 34