Download Experimentation

PSYCH JOURNAL 9/4/2013
 Sometimes people are strange. Psychology
sometimes explores the weird things people
do, and why they do them. What weird thing
about people would you like to learn more
about?
 How would you design an experiment to learn
more about some of the weird things people
do?
Research Methods
Psychology is first and foremost a science.
Thus it is based in research.
Scientific Method
The process for the empirical investigation of a hypothesis. Create
conditions that control biases and subjective judgments.
1. Hypothesis
2. Preform a controlled test
3. Gather objective data
4. Analyze the results
5. Publish, criticize, replicate
Theory
A theory is testable explanation for a set of facts or observations. A
theory arises from repeated observation and testing and
incorporates facts, laws, predictions, and tested hypotheses that
are widely accepted.
Ex: Motivation Theories
Instinct Theory
Drive Theory
Cognitive Theory
Hypothesis
A hypothesis is a specific,
testable prediction about what
you expect to happen in your
study.
It’s an educated guess, sometimes
written as an if/then statement,
that expresses a relationship
between two variables
If Jean participates in class, then
she will earn an A+.
Operational Definition
 Specific descriptions of concepts involving the conditions of a
study.
 People who smile are happier.
 What is happy?
 Happy is scoring a 55 or higher on a happiness survey.
Preforming a Controlled Test
Research would require us to conduct a study
to either confirm or disprove our hypothesis.
Experimentation
Exploring Cause and Effect
 Like other sciences,
experimentation is the
backbone of psychology
research. Experiments isolate
causes and their effects.
 The purpose of an
experiment is to determine how
a treatment affects a behavior.
Independent Variable
An Independent Variable is the factor that
researchers manipulate so they can determine
its effect. The effect of the independent
variable is the focus of the study.
Independent Variable (IV)
Whatever is being
manipulated in the
experiment.
Hopefully the
independent variable
brings about change.
If there is a drug in an
experiment, the drug
is almost always the
independent variable.
Dependent Variable (DV)
 Whatever is being
measured in the
experiment.
The dependent variable
would be the effect
of the drug.
 The factor that
changes in response
to the independent
variable
WHAT IS THE IV WHAT IS THE DV?
 A scientist studies the impact of a drug on cancer.
 The independent variable is the administration of the drug.
 The dependent variable is the impact the drug has on cancer.
 A scientist studies the impact of withholding affection on rats.
 The independent variable is the affection.
 The dependent variable is the reaction of the rats.
 A scientist studies how many days people can eat soup until they
get sick.
 The independent variable is the number of days of consuming soup.
 The dependent variable is the onset of illness.
Experimental Group
The Experimental Group is the group that RECEIVES the treatment
Treatment usually means the “weird” thing being done to a group
Control Group
The Control Group is the
group that does NOT receive
the treatment
We need this group to
compare to the experimental
group to see if the
independent variable created
an effect or not
My Experiment
 Theory: Students who OVERSTUDY do better in school.
 Hypothesis: If students re-write their notes, they will do better
on the chapter two exam.
 Independent variable: Studying using the technique of rewriting notes.
 Dependent variable: How students do on the exam.
 Experimental Group: Students who re-write notes
 Control Group: Students who do not re-write notes
Confounding Variables
If I wanted to prove that
smoking causes heart
issues, what are some
confounding variables?
Confounding Variables
are other variables that
could possibly be affecting
our experiment’s outcome
We want to MINIMIZE or
ELIMINATE these!!
Lifestyle and family
history may also
effect the heart.
Quick Experiment Creation
Theory: Breast-feeding causes higher intelligence
Hypothesis: Babies who are breast-feed will score higher on IQ tests than
those who are fed formula milk.
What would the IV, DV, Experimental Group, and Control Group be??
Experimentation
A summary of steps during experimentation.