Maria Vita
Free-Response Question to review research methods unit & sleep
Adapted from http://www.bbc.com/news/science-environment-34192371
Should school begin later?
Beginning in 2014, 100 schools in the United Kingdom were be randomly assigned to either a late-start time or a normal start time. The late-start students will begin their day at 10 am, while the others will begin as usual. The study will publish its final results in 2017.
Part I: Describe the parts of the study using the following terms.
a) Operationalize the independent variables.
b) Identify the control group.
Part II: Use the following terms to support a late-start to the school year
c) Circadian rhythms & melatonin
d) REM rebound
e) Activation information model
Part III: Pretend it is 2017 and the following results are reported. Use each to support a late start to the school year.
f) Illustrate and label a bar graph that shows how the late-start group averages higher grade-point-averages (GPAs) than the normal start group.
g) How does random assignment strengthen the researchers’ conclusions that students who start school late have improved grades?
h) If p < .05, what can researchers conclude?
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Point 1: When researchers operationalize a variable, they provide a list of quantifiable behaviors OR behaviors that can be counted. The independent variable is the thing being tested. The start time is being tested with either “normal” start time or “late” (10am) time.
Do not score: Start time alone
Point 2: Control group is the group used for comparison. Must identify as the “normal” start time and/or students who begin school as usual.
Point 3: Circadian rhythm is the body’s biological clock – it tends to control the release of hormones at certain times of the day. According to some research, teenagers produce melatonin (a hormone related to sleep) later in the evening. Therefore, teens may feel sleeper in the early mornings and more energetic later in the day.
Point 4: REM rebound –if someone is sleep deprived or gets chronic insufficient sleep the body seeks to restore slow-wave sleep (delta) as well as REM sleep as a restorative tool. The person sleeps deeper and longer. Teens may have chronic sleep debt if they are unable to get rest each night.
Point 5: Activation synthesis model – sleeping/dreaming may be necessary for memory creation and learning. Especially skill-based memories which improve with practice and sleep. Thus, a late-start could impact learning and memory.
Point 6: Bar graph labels –
Y-axis = dependent variable GPA
X-axis = start time
Point 7: Bar graph results
Late start must be higher
than normal start
Point 8: Random assignment strengthens conclusions because it eliminates confounding variables like intelligence, family income, gender, age, night-owls, larks, etc. Student must name specific variable that could interfere.
Point 9: p < .05
*The results were not by chance or not likely to occur under the null
*The null hypothesis can be rejected (reject that late-start has no impact)
Do not score: Results important or cause-and-effect claims