Evolutionary theories frequently emphasize that humans have adapted to their physical environment. One such theory hypothesizes that people must spontaneously follow a 24-hour cycle of sleeping as well as waking-even if they aren't exposed to the usual pattern of sunlight. To test this notion, eight paid volunteers were placed (individually) in the room in which there was no light from the outside as well as no clocks or other indications of time. They could turn lights on and off as they wished. After a month in the room, each individual tended to develop a steady cycle. Their cycles at the end of study were as follows: 25, 27, 25, 23, 24, 25, 26, and 25.
Using the .05 level of significance, what should we conclude regarding the theory that 24 hours is the natural cycle? (That is, does the average cycle length under these situations differ significantly from 24 hours?) (a) Employ the steps of hypothesis testing. (b) Sketch the distributions involved, (c) Discuss your answer to someone who has never taken the course in statistics.