An experiment is conducted to determine the effect of two di

An experiment is conducted to determine the effect of two different methods on measuring the concentration of a certain radioactive isotope in milk. Twenty specimens of milk are randomly selected from each of four dairies. The 20 specimens from each dairy are randomly divided into two groups of 10 specimens. Two methods for measuring the concentration of the isotope are randomly assigned to the two groups of specimens from each of the dairies. For some reason, a few of the specimens from the second and fourth dairy got damaged during transportation and had to be excluded from the analysis. The sample means together with the sample sizes available for each combination of dairy and measurement method are given below: Are these data balanced or unbalanced? Why? If you were to use a two-way ANOVA for these data, what would be the two factors? If you were to use a randomized complete block design for these data, what would be the blocking variable? Under the two-way ANOVA, how many treatments are there in this experiment? Describe (or simply name) one treatment. Which analysis (two-way ANOVA or CRBD) do you think is more appropriate for these data? Explain.

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