Research Methods in Psychology

advertisement
Essential Questions
• How do psychologists use the scientific
method to study behavior and mental
processes?
• What are the strengths and weaknesses of
the different research methods?
• How do psychologists draw appropriate
conclusions about behavior from research?
Growth
of
Psych
Approaches
to Psych
Careers
Ethics
Research
Methods
Sampling
Descriptive
Correlation
Naturalistic
Observation
Case
Study
Survey
The Science of
Psychology
We
are
here
Experiment
Statistics
Descriptive
Inferential
Growth
of
Psych
Approaches
to Psych
The Science of
Psychology
Careers
Ethics
Research
Statistics
Methods
Sampling
Descriptive
Correlation
Naturalistic
Observation
Case
Study
Survey
Experiment
We
are
here
Descriptive
Inferential
Research Methods
1. Description – gathering evidence about A and B
2. Correlation – A and B are related
3. Experiment – A causes B
Descriptive Research
DESCRIBES
Descriptive Research
• Purpose – To describe what is in reality
• Strengths
– Certain descriptive research methods can be quick
– You can generalize (apply to more than just those from
which you sampled) your findings with some
descriptive research methods
• Weaknesses
– Can’t help you predict
– Can’t give you cause and effect
– Each descriptive research method has their own
weaknesses as well
Be curious!
1. Does involvement in HS athletics improve academic
performance?
2. Does excessive texting impede face-to-face relationships?
3. Does personality influence musical preferences?
4. Do ads portraying unrealistic body types reduce the selfimage of the viewer?
5. Does student consumption of caffeine in the morning
improve first period grades?
6. Does gamification of the classroom improve increase
student engagement?
Be curious!
7. Does a community service requirement positively or
negatively impact student opinions of community service?
8. Do teacher websites improve student performance in class?
9. Does focus on minor rules (flip-flops and hats) reduce
student adherence to major rules (insubordination or class
cutting)?
Growth
of
Psych
Approaches
to Psych
The Science of
Psychology
Careers
Ethics
Research
Statistics
Methods
Sampling
Descriptive
Correlation
Naturalistic
Observation
Case
Study
Survey
Experiment
We
are
here
Descriptive
Inferential
Case Studies
• What is it? Study of a single individual or just a
few individuals in order to describe their situation.
• Purpose? Take advantage of situation that you
can not replicate (make happen again)
• How? Gather as much evidence as you can:
Observation, scores on psychological tests,
interviews, medical records etc.
Case Studies
• Tells us a great
story…but is just
descriptive
research.
*The ideal case study
is John and Kate.
Really interesting, but
what does it tell us
about families in
general?
Two most famous case studies in
psychology
Genie
Phineas Gage
The Lost Children of
Rockdale County
• Studied a Syphilis
epidemic at a high
school in an affluent
suburb of Atlanta
Growth
of
Psych
Approaches
to Psych
The Science of
Psychology
Careers
Ethics
Research
Statistics
Methods
Sampling
Descriptive
Correlation
Naturalistic
Observation
Case
Study
Survey
Experiment
We
are
here
Descriptive
Inferential
• Respond to each of the following statements with a
number from 1= strongly agree to 7= strongly disagree.
_____ 1. I oppose raising taxes.
_____ 2. The primary task of the government should
be to keep citizens safe from terrorism & crime.
_____ 3. I regularly perform routine maintenance on
my car.
_____ 4. I make it a practice to never lie.
_____ 5. Monogamy (not cheating on my significant
other) is important to me.
_____ 6. How often do you exercise?
1
2
3
Infrequently
Occasionally
Often
• Respond to each of the following statements with a number
from 1= strongly agree to 7= strongly disagree.
_____ 1. I’d be willing to pay a few extra dollars in
taxes to
provide high-quality education to all kids.
_____ 2. The primary task of the government should
be to preserve citizens’ rights & civil liberties.
_____ 3. Sometimes I don’t change the oil in my car
on time.
_____ 4. Like all human beings, I occasionally tell a
white lie.
_____ 5. Sexual freedom is important to me.
_____ 6. In the last 6 months, how often have you
engaged in at least 20 minutes of aerobic activity?
1=Almost Never. 2=Less than once/week. 3=once/week
4= 2x/week. 5= 3x/week. 6= 4x/week. 7= +4x/week
Survey
Wording Effect
Wording can change the results of a survey.
Q: Should cigarette ads and pornography be allowed
on television? (not allowed vs. forbid)
Surveys
– A technique for
ascertaining the selfreported attitudes,
opinions or behaviors of
people usually by
questioning a
representative, random
sample of people.
Strength: Can generate a lot
of information for a fairly
low cost
Weakness: Questions must
be constructed carefully so
as to not elicit socially
appropriate answers or
the wording effect. Plus,
people could lie!
Non-response/Volunteer Bias
• Women and Love study done by Shere Hite (1974)
• 98% Dissatisfied in their Marriage
• 75% Extramarital Affairs
• But to all of those who were
mailed surveys only 4%
responded.
When randomly sampled
• 93% of women are satisfied in their
marriages
• Only 7% had affairs
Survey
Random Sampling
From a population if
each member has an
equal chance of inclusion
into a sample, we call
that a random sample
(unbiased). If the survey
sample is biased, its
results are questionable.
The fastest way to know about the
marble color ratio is to blindly
transfer a few into a smaller jar and
count them.
Stratified Sampling
• When sub-populations vary considerably, it is
advantageous to sample each subpopulation
(stratum) independently. Stratification is the
process of grouping members of the population
into relatively homogeneous subgroups
before sampling.
• https://www.youtube.com/watch?v=i4639vev1R
w
Ashika (F, athletic, AP student, from Asia)
Kale (F, career prep, works after school,
Caucasian);
Deanna (F, auto-immune disease,
homeschooled, Latino);
Fred (M, drop-out, Caucasian);
Joe (M, depressed, AP student, American
Indian);
Bob (M, tall, athletic, likes to read, Latino)
Donny (M, obsessed with germs, takes
vitamins, good student, AfAmer);
Tom (M, loves music, hates school,
Caucasian)
Joy (F, nervous, anxiety disorder, absent from
school often, AfAmer);
Brenda (F, loves texting to b/f in school,
Latino)
Lyle (M, comes to school for socializing, hates
teachers, Latino);
Anthony (M, career-prep student, lazy,
Latino)
Nate (M, wants to own family business, AP
student, AfAmer)
Kandy (F, pregnant, might drop-out,
Caucasian)
Runa (F, AP Student, Quiz Bowl, Asian);
River (M, AP Student, Math Bowl, Golf,
Caucasian)
Levi (M, Honors student, athletic, Caucasian)
Layla (F, Honors student, volunteer,
AfAmerican)
Eli (M, avg. student, likes vo-tech mechanics,
Latino)
Tessa (F, athletic, unstable home, Asian)
Stella (F, loves to dance, avg. student,
Caucasian)
Nina (F, defiant toward adults, needs special
classes, Caucasian)
Sampling from a population
“The root of the problem is that in real life, all
scientists ever observe are samples. And, in real
life, all they want to know about is populations”
Nancy Darling, Ph.D.
Growth
of
Psych
Approaches
to Psych
The Science of
Psychology
Careers
Ethics
Research
Statistics
Methods
Sampling
Descriptive
Correlation
Naturalistic
Observation
Case
Study
Survey
Experiment
We
are
here
Descriptive
Inferential
Naturalistic Observation
• Watch subjects in their
natural environment.
• Do not manipulate the
environment.
• Naturalistic Observation
– The main drawback is
observer bias
• (expectations or biases of the
observer that might distort or
influence the interpretation of
what was observed.)
– Not replicable so you can’t
generalize
Hawthorne Effect
• Just the fact that
you know you are in
an experiment can
cause change.
Whether the lights were
brighter or dimmer,
production went up in the
Hawthorne electric plant.
Descriptive Methods Comparison
Research Method
Advantages
Limitations
Naturalistic
Observation
•More accurate than reports
after the fact
•Behavior is more natural
•Hawthorne Effect
•Observational Bias
•Cannot be generalized
Case Studies
•Depth
•Takes advantage of
circumstances that could not
be coordinated in an
experiment
•Not representative
•Time consuming and
expensive
•Observational Bias
Surveys
• Immense amount of data
•Quick and inexpensive
• Sampling biases can skew
results
•Bad Questions can corrupt
data
•Accuracy depends on the
ability and willingness of the
participants.
Download