Transcript Research Methods

Research Methods (8-10%)
https://www.youtube.com/watch?v=hFV7
1QPvX2I
Applied V. Basic Research
• Applied Research
has clear, practical
applications.
• YOU CAN USE IT!!!
• Basic Research
explores questions
that you may be
curious about, but
not intended to be
immediately used.
Studying how
kissing changes
when you get
older is
interesting…but
that’s about it.
Research on therapies for drug addicts has
a clear purpose.
Why do we have to learn this stuff?
Psychology is first and foremost a science.
Thus it is based in research.
Before we delve into how to do research, you should be
aware of three hurdles that tend to skew our logic.
Hindsight Bias
• The tendency to
believe, after
learning the
outcome, that you
knew it all along.
After the Chris Brown/Rihanna
incident….lots of people said
they knew Chris Brown was a
violent guy… Did they really?
Monday Morning
Quarterbacking!!!
Overconfidence
• We tend to think we
know more than we do.
• 82% of U.S. drivers consider
themselves to be in the top 30% of
their group in terms of safety.
• 81% of new business owners felt
they had an excellent chance of
their businesses succeeding. When
asked about the success of their
peers, the answer was only 39%.
(Now that's overconfidence!!!)
The Barnum Effect
• It is the tendency for
people to accept very
general or vague
characterizations of
themselves and take
them to be accurate.
– Examples:
• Horoscopes
• Fortunes
• Year of ____ “place mat”
Terminology
Theory
• An explanation
using a set of
principles that
organizes / predicts
behaviors or
events.
Hypothesis
• Expresses a
relationship between
two variables.
• A variable is anything
that can vary among
participants in a study.
• Participating in class
leads to better grades
than not participating.
The Need for Psychological Science
Independent Variable
• 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
• Whatever is being
measured in the
experiment.
• It is dependent on the
independent variable.
The dependent variable
would be the effect
of the drug.
Psychology’s Research Strategies
• Psychology’s research strategies include
descriptive, correlational and experimental
• Pg. 40-study
Descriptive
Case Study
 Psychologists
study one or more
individuals in great
depth in the hope
of revealing things
true of us all
Is language uniquely human?
Case Studies
• A detailed picture of
one or a few
subjects.
• Tells us a great
story…but is just
descriptive
research.
• Does not even give
us correlation data.
The ideal case study is John and
Kate Plus 8. Really interesting, but
what does it tell us about families
in general?
Descriptive
 Survey
 technique for ascertaining the self-reported
attitudes , opinions or behaviors of people
 usually by questioning a representative, random
sample of people
 Random Sample
 a sample that fairly represents a population because
each member has an equal chance of participating
 Ex- survey calls or individuals outside of stores
Survey Method
•Most common type of
study in psychology
•Measures correlation
•Cheap and fast
•Need a good random
sample
•Low-response rate
Descriptive
 Naturalistic
Observation
 observing and
recording behavior in
naturally occurring
situations without
trying to manipulate
and control the
situation
 Ex- animals, children
in their home or
schools
Correlation
 Correlation Coefficient
 a statistical measure of the extent to which two factors vary together, and
thus how well either factor predicts the other.
 Ex-knowing how much aptitude test score correlate with school
success tells us how well the scores predict school success
Indicates direction
of relationship
(positive or negative)
Correlation
coefficient
r = +.37
Indicates strength
of relationship
(0.00 to 1.00)
Correlation
 Scatterplot
 a graphed cluster of dots, each of which represents
the values of two variables
 the slope of the points suggests the direction of the
relationship p.31
 the amount of scatter suggests the strength of the
correlation
 little scatter indicates high correlation
 also called a scattergram or scatter diagram
Correlation
Perfect positive
correlation (+1.00)
No relationship (0.00)
Perfect negative
correlation (-1.00)
Scatterplots, showing patterns of correlations
Types of Correlation
Positive Correlation
• The variables go in
the SAME direction.
Negative Correlation
• The variables go in
opposite directions.
Studying and
grades hopefully
has a positive
correlation.
Heroin use and
grades probably has
a negative
correlation.
Correlation
Three Possible Cause-Effect Relationships
(1)
Low self-esteem
could cause
Depression
or
(2)
Depression
could cause
Low self-esteem
or
Low self-esteem
(3)
Distressing events
or biological
predisposition
could cause
and
Depression
Experimentation
 Experiment
 an investigator manipulates one or more
factors (independent variables) to observe
their effect on some behavior or mental
process (the dependent variable)
 by random assignment of participants the
experiment controls other relevant factors
Sampling
• Identify the
population you want
to study.
• The sample must be
representative of
the population you
want to study.
• GET A RANDOM
SAMPLE
Experimentation
 Placebo
 an inert substance or condition that may be
administered instead of a presumed active agent, such
as a drug, to see if it triggers the effects believed to
characterize the active agent
 Double-blind Procedure
 both the research participants and the research staff
are ignorant (blind) about whether the research
participants have received the treatment or a placebo
 commonly used in drug-evaluation studies
Random Assignment
• Once you have a
random sample,
randomly assigning
them into two groups
helps control for
confounding variables.
• Experimental Group v.
Control Group.
Beware of
Confounding Variables
If I wanted to prove that
smoking causes heart
issues, what are some
confounding variables?
• The object of an
experiment is to prove
that A causes B.
• A confounding variable
is anything that could
cause change in B, that
is not A.
Lifestyle and family
medical history may
also effect the
heart.
Operational Definitions
• A statement of procedures
used to define research
variables.
• Explain what you mean in
your hypothesis.
• How will the variables be
measured in “real life”
terms.
• How you operationalize the
variables will tell us if the
study is valid and reliable.
Let’s say your hypothesis is
that chocolate causes
violent behavior.
• What do you mean by
chocolate?
• What do you mean by
violent behavior?
Hawthorne Effect
• But even the control group
may experience changes.
• Just the fact that you
know you are in an
experiment can cause
change.
• http://psychology.about.co
m/od/hindex/g/def_hawt
horn.htm
Whether the lights were brighter or
dimmer, production went up in the
Hawthorne electric plant.
Experimentation
Statistics
• Once data is gathered
we must organize,
summarize and make
inferences from it using
statistics.
• Recording the results
from our studies.
• Must use a common
language so we all know
what we are talking
about.
Statistical Reasoning
 Mode
 the most frequently occurring score in a distribution
 Mean
 the arithmetic average of a distribution
 obtained by adding the scores and then dividing by the
number of scores
 Median
 the middle score in a distribution
 half the scores are above it and half are below it
Normal Distribution
• In a normal
distribution, the
mean, median and
mode are all the
same.
Distributions
• Outliers skew
distributions.
• If group has one high
score, the curve has a
positive skew
(contains more low
scores)
• If a group has a low
outlier, the curve has
a negative skew
(contains more high
scores)
Statistical Reasoning
 Range
 the difference between the highest and lowest scores
in a distribution
 Standard Deviation
 a computed measure of how much scores vary around
the mean
 Statistical Significance
 a statistical statement of how likely it is that an
obtained result occurred by chance
Other measures of variability
• Range: distance from
highest to lowest scores.
• Standard Deviation:
the variance of scores
around the mean.
• The higher the variance
or SD, the more spread
out the distribution is.
Lebron and Wade
may both score 30
ppg (same mean).
But their SDs are
very different.
Ethics in Research
Animal Research
• Clear purpose
– b/c human physiology resembles
various animals (esp. mammals)
– Some experiments are not
permitted on humans
• Treated in a humane way
• Acquire animals legally
• Least amount of suffering
possible.
Rats, mice, rabbits and
birds are the types of
animals often used in
psych researech
Ethics Human Research
• No Coercion- must be
voluntary
• Allow them to withdraw @
any time
• Informed consent
• Protect from harm &
discomfort
• Must debrief
• Protect confidentially
MILGRAM OBEDIENCE Experiment
Ethical or unethical? pg. 706
• 1. Now that you know about
• Stanley Milgram –Social ethical guidelines for
conducting human research,
psychologist.
while watching the video,
• Studies about social
describe 3 ethical guidelines
interaction and
that would be violated if this
experiment was conducted
obedience
today.
• 2. Discuss and explain how you
• Discussion about
would have responded as a
obedience?
subject in the experiment?
(giving the “electrical shocks”
and as the individual that
“received” the electrical shocks
Zimbardo Prison experiment
• Page 700
Read
https://www.youtube.com/watch?v=1jdOoxnr7AI
• Also Milgram obedience experiment pg. 706
Normal Distribution
Scores
• A unit that measures
the distance of one
score from the mean.
• A positive z score
means a number above
the mean.
• A negative z score
means a number below
the mean.
Statistical Reasoning
A Skewed Distribution
15 20 25 30 35 40 45 50
90
475
70
Mode Median
One Family
Mean
Income per family in thousands of dollars
710