Research Methods in
Psychology
Chapter 1
The Scientific Method
And so much more
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Psychology…
The science of behavior
Two connotations of science
1) Content (what we know)
2) Process (an activity that includes)
a) gathering data
b) noting relationships
c) offering explanations
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IS Red Wine good for you, even though it
doesn’t have much resveratrol?
http://www.podcastdirectory.com/podshows/2256667 forward to
23.30
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Scientific methods…
1) Specifying conditions
2) Systematic observation
3) Explanations of behavior
Methodology…
Scientific techniques used to collect
and evaluate data (the facts and
figures gathered in research studies).
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Methods include:
Everything in Methods section of paper
Subjects, Apparatus and Procedures
And ‘methods’ used in Results section
data transforms, statistical techniques, p
values
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Commonsense psychology…
The kind of everyday, nonscientific data
gathering that shapes our expectations,
beliefs and directs our behavior toward
others (Heider, 1958).
Summer internship in Paris…
“absence make the heart grow fonder”
or “out of sight, out of mind”
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Constraints:
1) Source of information
2) Inferential strategies
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Nonscientific sources of data…
although seemingly trustworthy (e.g.,
friends, family, people we admire, books
or even news reports), are not always
very good sources for obtaining valid
information.
Is there any source that is?
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What about this guy?
E=
2
MC
God doesn’t
roll dice with
the Universe
Any truthiness to superstitions…
If you believe that the full moon triggers
“lunacy” you might notice and remember
abnormal behaviors more and ignore the
many more instances of no abnormal
behavior during this lunar event.
However, we can’t avoid all superstitions,
myths and urban legends…
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Any truth to superstitions…
Apparently, there is some scientific evidence
to support the belief that Friday the 13th
is unlucky!
Scanlon, Luben, Scanlon, & Singleton, 1993
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Scanlon et al. 1993…
Retrospecitive study comparing
Group A: Fri 13 to Group B: Fri 6th
Measures
vehicles on motorways
shoppers in supermakets
hospital admissions due to car accidents
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Scanlon et al. 1993…
Results
Fewer vehicles on highway on Fri 13
Number of shoppers were the same
Increased hospital admission due to Auto
accident on Fri 13
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Nonscientific inference…
Exercise… Pick someone in the room who you
perceive to be different from you.
Together, create a list of the actual differences
between you and your partner. (5 min.)
Next, create a list of the commonalities
between you and your partner. (5 min.)
Tally the number of differences and the number
of similarities.
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Result of exercise…
You’re suppose to learn that you have more
in common than you initially thought…
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Nonscientific inference…
As commonsense psychologists, we are trait
theorists.
Perceiving others in terms of their traits can
lead to overestimations of the likelihood that
they will act in certain ways in a wide variety
of situations.
Inferential biases are believed to be the brain’s
way of coping with an immense amount of
information.
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Scientific mentality…
Alfred North Whitehead traced the
development of science in his book Science
and the Modern World (1925). He postulated
that “faith” in an organized universe is
essential to science.
Research psychologists share the belief that
there are specifiable reasons for the way
people behave.
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Empirical data…
Observable or experienced data are preferable
to commonsense data, but does not
guarantee that correct conclusions will be
reached.
Modern scientists propose general principles –
laws or theories - to explain observable data.
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General principles…
Laws are applicable to all situations.
Theories pull together groups of scientific facts
into an organizing scheme or set of rules.
Science progresses only through progressively
better theories. ( Popper, 1963)
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Good thinking…
Collection and interpretation of data should be
systematic, objective and rational.
Avoid letting private beliefs or expectations
influence observations or conclusions.
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Pre-conceptual science…
Comics: Non Sequitur
M&H call it woodenheaded thinking
“…assessing a situation in terms of preconceived fixed notions
while ignoring or rejecting any contrary signs. (Tuchman,
1984, p. 7).”
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Pre-conceptual science…
Comics: Non Sequitur
M&H call it woodenheaded thinking
“…assessing a situation in terms of preconceived fixed notions
while ignoring or rejecting any contrary signs. (Tuchman,
1984, p. 7).”
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Pre-conceptual science…
Comics: Non Sequitur
M&H call it woodenheaded thinking
“…assessing a situation in terms of preconceived fixed notions
while ignoring or rejecting any contrary signs. (Tuchman,
1984, p. 7).”
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Good thinking…
Principle of Parsimony, a.k.a. Occam’s Razor
“entities should not be multiplied without
necessity”
Avoid unnecessary assumptions to support a
hypothesis. When two explanations are
equally defensible, the simplest explanation is
preferred until conflicting data rules it out.
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Self-correction…
Science involves a constant re-evaluation of
concepts and explanations.
Falsification – challenging existing explanations
and theories by testing hypotheses that
follow logically from them.
modus tollens (procedure of falsification) – it
only takes one case of a contrary instance to
prove a statement false.
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Publicizing results…
Scientists publish their results in scientific
journals and report findings at professional
conferences.
Reporting scientific findings is very important
to avoid unnecessary duplication of
experimental work.
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Replication…
Replicating experimental work ensures that a
result can be reproduced, which sometimes
does not happen and may even reveal
scientific misconduct.
As we shall see in the documentary:
The Dark Secret of Hendrik Schön
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The Tools of Psychological Science
Observation – systematic recording of events.
Measurement – assigning numerical value to
events and objects according to conventional
rules or standards.
Experimentation – is a process to show that
certain events are predictable under certain,
specifiable conditions.
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Experimentation
Can only be done if a prediction is testable.
Two minimum requirements
1. procedures for manipulating the setting
2. the predicted outcome must be observable
Drug A increases…
dreaming
spatial mapping
anxiety
etc.
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Scientific Explanations in
Psychological Science
Antecedent conditions – circumstances that
come before an event or behavior.
Treatment conditions – antecedent conditions
that we create in an experiment.
The psychology experiment – a controlled
procedure in which at least two different
treatment conditions are applied to the
subjects.
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Establishing cause and effect…
1) If the experiment has adequate control AND
2) If the two treatments result in differences in
the behavioral measure, THEN
3) We can infer a cause and effect relationship
(antecedent  outcome)
4) This is always stated in terms of the
probability or likelihood that the treatment
caused the behavioral difference between
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subjects.
The Colbert Nation:Truthiness
A statistically sound scientific concept!
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