Chapter 4.2, Problem 72E

(a)

To determine

To describe a randomized block design for this experiment and also justify your choice of block.

Explanation of Solution

In this study, an agriculture researcher wants to compare the yield of five corn varieties: A, B, C, D and E.These experiment will be carried out to see if the fertility of the crop increases from north to south.

A randomized block design can group the subjects into blocks which have a common characteristic and thus a randomized block design allows us to take into account the change of one or more extra variables.

The agriculture researcher wants to test the fertility of the corn varieties. Thus in this case the blocks will be the fertility of the area that is divided in plots. It will allow us to take into account the fertility of the area where the plots are.

(b)

To determine

To explain why a randomized block design might be preferable to a completely randomized design for this experiment.

Explanation of Solution

In this study, an agriculture researcher wants to compare the yield of five corn varieties: A, B, C, D and E.These experiment will be carried out to see if the fertility of the crop increases from north to south.

A randomized block design might be preferable to a completely randomized design for this experiment because randomized block design can group the subjects into blocks which have a common characteristic and thus a randomized block design allows us to take into account the change of one or more extra variables.

Thus we can then best use blocks based on how overweight the subjects are, because the alphabetical order has no interesting characteristics that we want to investigate.