Thinking About Developmental Research
Planning and conducting a good research project is hard work. There are many
possible pitfalls along the way – and there’s always a chance that results may not
support the researcher’s hypothesis. This activity will test your knowledge of some
of the common pitfalls in developmental research.
Research Goals
When designing a new study, researchers generally adopt one of three types of
methods, depending on the goal of their study.
 Descriptive Approach
If the goal is to describe or document a particular behavior, researchers
rely on the descriptive approach – a method of investigation used to
observe, measure, and describe behavior.
 Correlational Approach
If the goal is to predict the occurrence of a particular behavior,
researchers use the correlational approach – a method that measures
two different types of behavior and evaluates the relationship
between them.
 Experimental Approach
If the goal is to explain a behavior or understand why it occurs,
researchers turn to the experimental approach – a method of
investigation used to demonstrate a cause-and-effect relationship by
purposely manipulating one aspect of a situation that is thought to
produce change in a particular behavior.
Research Pitfalls
You will be presented with a brief description of four studies. Each study has one major
methodological flaw and possibly other minor problems.
Your task, after reading the descriptions, is to answer the following questions:
1. What is the broad goal of this study?
2. What’s wrong with this study?
3. How could it be improved?
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First read the study and think about how you would answer these questions.
Next, discuss your ideas with your group members. These means explaining why you see it
the way you see it. Be able to justify your thinking. Use correct terminology in your
discussion.
Listen and consider other group members’ ideas.
Make sure everyone in the group shares his/her thoughts.
Come to a group consensus of your answers.
Research Pitfalls: Study 1
Study 1: Vocabulary Growth
Professor Jones wants to study vocabulary growth in
preschool children. He contacts all his faculty colleagues
who have children, and from this group he assembles a
sample of 20 children ranging in age from 2 years to 5 years.
To test each child’s word knowledge, Professor Jones reads
each child a list of simple words he has gathered from
children’s storybooks and records whether or not the child
understands each word. He then uses the results to publish
norms (standard or expected levels of achievement)
for vocabulary mastery for each year, from 2 to 5 years of age.
1. What is the broad goal of this study? (Choose One)
A. Descriptive: to describe development or typical age-related behaviors.
B. Correlational: to predict development or predict a particular aspect of behavior
C. Experimental: to explain development or particular aspect of behavior (cause-and-effect)
2. What’s wrong with this study? From list of flaws below, select the major flaw.
o no control group
o biased non-representative sample
o interpreting a correlation as indicating cause and effect
o experimenter bias
o participant bias
3. In your own words, explain why it’s the single most important flaw in this study’s design
or interpretation.
4. In your own words, describe how the study could be improved to eliminate the weaknesses
(or at least the major flaw).
Research Pitfalls: Study 2
Study 2: Learning to Share
Professor Okamoto is interested in the effects of prosocial
TV on sharing behavior among preschool children.
(Prosocial actions are meant to benefit others, not oneself.)
She assembles a sample of 100 children, then assigns each
child at random to either the prosocial TV group or the
neutral TV group. The first group then views 30 minutes
of TV with a prosocial theme, and the second group views
30 minutes of TV with a neutral theme. After the children
finish their TV session, Professor Okamoto assigns them to
“play groups” of 5 children from the same TV group. She
observes the small groups at play, and rates each child on the
tendency to share toys with other children.
1. What is the broad goal of this study? (Choose One)
A. Descriptive: to describe development or typical age-related behaviors.
B. Correlational: to predict development or predict a particular aspect of behavior
C. Experimental: to explain development or particular aspect of behavior (cause-and-effect)
2. What’s wrong with this study? From list of flaws below, select the major flaw.
o no control group
o biased non-representative sample
o interpreting a correlation as indicating cause and effect
o experimenter bias
o participant bias
3. In your own words, explain why it’s the single most important flaw in this study’s design
or interpretation.
4. In your own words, describe how the study could be improved to eliminate the weaknesses
(or at least the major flaw).
Research Pitfalls: Study 3
Study 3: Sleep and Academic Performance
Dr. Rivera wondered whether lack of sleep was related to
academic performance. He asked the 24 junior high school
students in his class to keep a diary for one month, and to
record the number of hours they slept each night and the
grades they received on each exam or assignment they
completed during that month. At the end of the month, Dr.
Rivera collected the diaries and compiled data for each
student, linking grades to the number of hours of sleep on
the day preceding the exam or assignment. He discovered
that students who got the most sleep had the highest grades,
and those with the least sleep had the lowest grades.
Dr. Riviera concluded that poor sleep habits reduce teens’
ability to learn.
1. What is the broad goal of this study? (Choose One)
A. Descriptive: to describe development or typical age-related behaviors.
B. Correlational: to predict development or predict a particular aspect of behavior
C. Experimental: to explain development or particular aspect of behavior (cause-and-effect)
2. What’s wrong with this study? From list of flaws below, select the major flaw.
o no control group
o biased non-representative sample
o interpreting a correlation as indicating cause and effect
o experimenter bias
o participant bias
3. In your own words, explain why it’s the single most important flaw in this study’s design
or interpretation.
4. In your own words, describe how the study could be improved to eliminate the weaknesses
(or at least the major flaw).
Research Pitfalls: Study 4
Study 4: Language Instruction
Professor Knapp wanted to test the effect of a new method of
Second language instruction for young adults speaking only
one language. She introduced the new method in all three
of her spring semester German classes. At the end of the
semester, she averaged the students’ grades. Since the overall
average was a B, she concluded that the new method enhanced
acquisition of the second language.
1. What is the broad goal of this study? (Choose One)
A. Descriptive: to describe development or typical age-related behaviors.
B. Correlational: to predict development or predict a particular aspect of behavior
C. Experimental: to explain development or particular aspect of behavior (cause-and-effect)
2. What’s wrong with this study? From list of flaws below, select the major flaw.
o no control group
o biased non-representative sample
o interpreting a correlation as indicating cause and effect
o experimenter bias
o participant bias
3. In your own words, explain why it’s the single most important flaw in this study’s design
or interpretation.
4. In your own words, describe how the study could be improved to eliminate the weaknesses
(or at least the major flaw).