Scientific & Research
Methods in Psychology
Initial Observation
• Media reports of victims who did not
receive help…
Logical Analysis = Why?
• Why did victims not receive help, despite
the presence of many bystanders? Could a
critical factor be diffusion of responsibility?
Testable Hypothesis
• If subjects are confronted with an apparent
emergency, then the likelihood of them
helping and the speed with which they
intervene should be reduced as the number
of fellow bystanders increases.
New Observations
{Research}
• The number of bystanders is manipulated in
a series of laboratory and field studies in
which various “emergencies” occur. The
results of these studies support the
hypothesis.
Theory-Building
• These findings result in a Theory of Social
Impact which relates diffusion of
responsibility and other group processes to
a variety of social phenomena.
New Hypotheses & Observations
Derived from the Theory
• The case of Kitty Genovese
Hypothesis
• A statement of the results a researcher
EXPECTS!!!
• A testable prediction, often implied by a
theory.
*i.e.: If you eat an apple every day then you
will keep the Doctor away.
Subjects
• People (or animals) on whom studies are conducted
• Population: all the cases in a group being studied,
from which samples may be drawn. *Note: Except
for national studies, this doesn’t refer to a country’s
whole population.
• Random Sample: Sample that fairly represents a
population because each member has an equal
chance of inclusion
– Random Sampling: choosing at random participants from a larger
population. Random samples are chosen for research ie:surveys,
interviews, experiments
– Randomm Assignment: involves taking a randomly chosen sample
& assigning the participants at random to either the experimental or
control group in an experiment. Random assignment ONLY
APPLIES TO EXPERIMENTS.
Variables
• Independent Variable: The factor the
researcher changes or manipulates in a
study. (I.V.)
• Dependent Variable: The factor in the
study that changes or varies as a result of
the manipulations in the independent
variable. (D.V.)
• Confounding Variable: A factor other than
the independent variable that might produce
an effect in an experiment
Say WHAT???!!!
• How can you tell which is the I.V. & which is the
D.V.?
• Most hypotheses contain the words if & then.
• i.e.: IF you eat an apple every day, THEN you
will keep the Doctor away.
• IF refers to the I.V. (what is controlled)
• THEN refers to the D.V. (what is measured)
Other important factors of the
research process…
• Control Group: This group of subjects DO
NOT participate in the critical party of the
study.
*i.e.: Subjects would receive a placebo.
• Experimental Group: These subjects DO
take part in the crucial part of the study.
*i.e. Subjects would receive the actual
medicine.
• Placebo: A “fake medicine” or sugar pill that
has no active ingredients & works by the
power of suggestion…or not at all!
***Operational Definition***
• A statement of the procedures (operations)
used to define research variables.
– i.e.: human intelligence; happiness; popularity;
good music; love; road rage….
Now you try it…
• If a request is made by a person in uniform
(like a policeperson), then more people will
agree to a request made by someone with a
uniform.
Make it a Single or a Double?
• Single-Blind Study: Subjects don’t know
to which group (control/experimental) they
belong, but the researcher does.
• Double-Blind Study: Neither participants
nor researchers know to which group any
subject belongs.
Research Methods in Psychology
• Survey Method: Involves asking subjects
questions about their feelings, opinions or
behavior patterns.
*i.e.: Mail, Face-to-Face, Phone, Internet…
*Pro: Can reach a very large population and gather
info quickly
*Con: Skewed results based on who replies;
Sorting fact from fiction; Truly representative?
• Naturalistic Observation: Researchers secretly
observe the subjects of the study in daily activity,
carefully recording their behavior.
*Advantage: Subjects behave as they normally do
*Disadvantage: Observer is not able to
talk/interact with the subject.
Naturalistic Observation
More Research Methods…
• Case Study: Research that collects lengthy,
detailed info. About one person’s
background, usually for psych. Treatment.
• Interviews: Researcher meets subject(s)
face to face and asking ?s.
*Advantage: Personal & detailed info. gathered
*Disadvantage: Sorting fact from fiction
And Even More…
• Cross-Sectional Study: Research that
looks @ different age groups @ the same
time in order to understand changes that
occur.
• Longitudinal Study: Studies the same
group of people over an extended period of
time.
Ghosting…
Scientific Method &Monty
Python
• https://www.youtube.com/watch?v=k2Mh
MsLn9B0