Chapter 4: Q 88. (page 259)

Wake-up call Do people naturally wake up earlier when they set an alarm before going to sleep? Justin decides to conduct his own experiment to find out. On Friday and Saturday nights, he doesn’t set the alarm before going to bed. On Monday and Tuesday, he sets the alarm for $7$ a.m. Justin records the time when he wakes up each day and then compares his average wake-up time with and without the alarm.
(a) Identify any flaws you see in the proposed design for this experiment.
(b) Describe how you would design the experiment. Explain how your design addresses each of the problems you identified in (a).

Short Answer

Expert verified

(a) The flaws are Justin do not set alarm in weekend. More than two repetitions must be allowed for the experiment.

(b) Select randomly two days on which you set alarm and other two days when you don't set alarm. Determine average wake time and compare it with or without alarm.

Step by step solution

Given Information

Researchers want to determine do people naturally wake up earlier when they set alarm before going to bed or not. Justin put alarm on weekdays and weekdays, not on weekends. On Monday, he sets alarm for $7$ am.

To identify flaws in proposed design.

The flaws can be:

Justin does not set alarm on weekends. Generally, we do not have to wake up early on weekend as compared to weekdays.
It should also allow repetitions more than twice for each experiment.

To describe how to design the experiment explain how the design addresses each of the problems you identified in (a).

Perform the experiment for five weeks.
Set alarm on Monday, Tuesday, Friday and Saturday.
Randomly pick two days of each week on which we set you alarm and don't set alarm for other two days. Record wake up time everyday.
Compare this average wake time with and without alarm.