Calcium and the bones of young girls. Calcium is important to the bone development of young girls. To study how the bodies of young girls process calcium, investigators used the setting of a summer camp. Calcium was given in punch at either a high or a low level. The camp diet was otherwise the same for all girls. Suppose that there are 50 campers.
(a) Outline a completely randomized design for this experiment.
(b) Describe a matched pairs design in which each girl receives both levels of calcium (with a "washout period," during which they eat their normal diet, between the times they receive each level of calcium). What is the advantage of the matched pairs design over the completely randomized design?
(c) The same randomization can be used in different ways for both designs. Label the subjects 01 to 50. You must choose 25 of the 50. Use Table B at line 110 to choose just the first 5 of the 25. How are the 25 subjects chosen treated in the completely randomized design? How are they treated in the matched pairs design?