Introduction
to Experimentation (Ch. 8)
internal
and external validity
Types of manipulation (environmental, instructional, invasive)
Pilot studies, manipulation checks
types of variance (nonsystematic (random error), systematic (confound),
and variance associated with IV)
sources of error and ways to reduce
confounds/extraneous variables
threats to internal validity (and how related to developmental studies):
history, maturation, etc
importance of experimental control (why important?)
experimental group/control group
random assignment vs. random sampling
selection of participants
experimenter effects
(experimenter characteristics, experimenter expectancies)
participant characteristics (demand characteristics, response bias)
ways
to reduce error and increase experimental control
(random
assignment, elimination of unwanted variables, constancy,
counterbalancing)
double blind experiments
placebo effect
Descriptive
Statistics (Ch. 5)
descriptive vs. inferential statistics
measures of central tendency (mean, median, mode)
variability (range, variance, standard deviation)
relationship
between variance/standard deviation and the mean
**variance (s2) and standard
deviation (s) -
: be able to compute and interpret
frequency
distributions
pictorial representations of data (histograms, bar graphs, frequency
polygons)
**z-zcores
and the normal distribution - be able to compute and interpret
outlier
**formula
provided; bring calculator
Correlational
Designs (Ch. 6)
correlational studies vs.
experiments
scatterplots
problems with correlations (restricted range, outliers, lack of
reliability, correlation vs. causation)
correlation coefficients - be able to interpret
positive, negative (inverse) relationships
correlation vs. causation and third variables
Ethics
(Ch. 14 + guiding questions from chapter)
informed
consent/problems obtaining informed consent
balancing benefits and costs
Deception - when can/should you use deception?
debriefing
invasion of privacy/confidentiality
coercion to participate
physical and mental harm/risk
courtesy
scientific misconduct
special
considerations in doing research with children
Institutional
Review Boards
in-class discussion
+ guiding questions
External validity, generalizability (
supplementary reading #3)
:
external validity
ecological validity
conceptual and
exact replication and importance of replication in science
relative benefits of lab and field studies
types of generalization (e.g., population, setting, time of interest)
threats to external validity (based on methods and participants)
ways to improve external validity and why/when should we?
Short
Essay
One
of the following questions will be selected for the essay portion of the
exam.
- Consider the following study:
A
social psychologist wants to investigate whether a
particular intervention is successful in helping children's social skills,
skills that may help them to form and keep friendships in the classroom.
He recruits two 4th grade classrooms at a local school. In one class, he
receives the teacher's permission to hold a series of fun role-playing
sessions designed to expose children to important social skills. The other
4th grade class receives no such training. At the end of the intervention
period, he tests the children's social skills in both classrooms with an hour-long battery
of tests of social skills. One class is tested before lunch, and the other
is tested after lunch, on the same day. The children in the intervention
classroom show significantly higher scores on the battery of tests. He
concludes that her intervention works to improve the 4th
graders' social skills.
Write an essay addressing the following questions:
-
Identify the independent and
dependent variable in the study.
-
What is internal validity and what
threats to internal validity are present in the study as it has been
conducted?
-
Can the researcher conclude that
her intervention helped the children (why or why not?) What extraneous
variables has the researcher failed to control for?
How could the study be re-designed to reduce the effects of
these variables?
-
Consider
the following research question:
An educational
psychologist believes that parental involvement in children’s
schooling improves student academic performance. Specifically, she
believes that when parents supervise their child’s homework and
check it for accuracy, there will be better student grades.
Design two studies
that test this question: one that is correlational and one that
is experimental. Include a brief description of the measures you
would use and be sure to identify the independent and dependent
variables, if applicable. What is the difference between these two
studies in what they allow you to conclude about the relationship
between parental involvement and academic performance? What are the
advantages and disadvantages of these two different designs?