Psychological Research
Take out all of your writing utensils
Average/Mean for females?
_____
Average/Mean for males?
_____
What can we conclude from this data?
Is our data scientific?
The Need for
Psychological Science
The biases and errors of people’s everyday judgments
illustrate the need for a scientific attitude:
A.
Skepticism
Where is the evidence?
How do you REALLY know this?
B.
Humility
Scientists are willing to reject their own
ideas/biases, if needed.
The Need for Psychological Science
C. Critical Thinking
 Scientists never blindly accept
arguments and conclusions
 Four elements
1.
2.
3.
4.
examine assumptions
discerns hidden values
evaluates evidence
assess conclusions
Trepanation
Chipping away a hole in the skull to let out evil spirits is
a cure for adolescent rebellion and the thinking that
leads adolescents to behave badly.
https://www.youtube.com/watch?v=YoU_-ru8yEc
1. Examine Assumptions
2. Discern Hidden Values
3. Evaluate Evidence
4. Assess Conclusions
The Need for Psychological Science
Critical Thinking Reduces  Hindsight Bias
 we tend to believe, after learning an outcome, that we
would have foreseen it
 the “I-knew-it-all-along” phenomenon
 Intuition
 Describe your intuitive moment
 In research, common sense (intuition) predicts what DID
happen more often than what WILL happen.
 Intuition is based on common sense and experience!
The Need for Psychological Science
 Overconfidence
 we tend to think we know more than we do
 Confirmation Bias
 our overconfidence leads us to CONFIRM
our own thoughts and ignore evidence that
might disprove us (bias)
 Have you ever ignored evidence that was
contrary/different from what you believed?
The Scientific Method
Used to accomplish the four goals –
a.
Describe M.P. and beh
b.
Explain M.P. and beh
c.
Predict M.P. and beh
d.
Control (help)
The Scientific Method
 Theory – organized set of principles
 Hypothesis – testable guess derived from theory
 Operational Definition
How can you measure or “operate” with these
variables?
Test the hypothesis:
Girls smile more than boys.
The Need for Psychological Science
Operational Definitions
 I want to study the effects of physical contact on
attachment.
 I want to study the effects of sugar on attention
levels.
 Watching television as a toddler leads to
decreased ability to focus as an adult.

What are the variables?

How will you measure them?
Six steps of the Scientific Method.
a. Identify the theory
b. Form an hypothesis
c. Determine the variables
d.Design the experiment
e. Gather the data
f. Analyze, conclude, and
report your findings
Journals, Colleagues
Magazines
g. Replicate = Validity
Case Study
Survey
Naturalistic Observation
Correlation
Experimentation
Free Response 2006 Exam
Psychologists use a variety of research methods to study behavior.
Three of the main research methods used are:
*
Case Study
*
Correlational Study, and
*
Experiment.
A. Discuss the advantage of each research method listed above.
B. Discuss one disadvantage of each research method listed above.
Pretend you are a psychologist who will use each of the three research methods
– case study, correlational study, and experiment—to determine the effect of
taking Vitamin J on improving memory.
C. For each method listed above, explain a key characteristic of the basic approach
you could use to reach a scientific conclusion about the relationship between
taking vitamin J and improving memory. You need not design a complete
study.
Case Study
 Goals Met  Description (of the ONE person or ONE small group)
Definition:
Advantages:
Intensive analysis and description of
an individual or a small group.
A lot of information.
A rich description.
Leads to ideas for future study.
Case Study Continued …
Disadvantages
 Observer Bias
 Difficult to generalize beyond
single case studied
https://www.youtube.com/watc
h?v=_6Fv_P-lKYU
Examples
Reflection Question #3…
Goals Met: Describe and Predict (if correlation
determined from data)
Definition: Asking predetermined questions using
an interview or a questionnaire.
Survey Continued …
Advantages
Disadvantages
 Lots of information
 Respondents might not be
 Relatively low cost
representative (sampling
bias)
 Respondents might not be
knowledgeable or might want
to please researcher (response
bias)
 Done in a short amount of
time
Survey Problems …. 
 Response Bias – What
people SAY is often very
different from what the
DO. (Would you admit to
everything you
do/think/feel?)
 False Consensus – The
tendency to overestimate
the extent to which others
share our beliefs and
opinions.
Types of Wording Effects
 Wording Effects – The
way a question is worded
affects the outcome of
the survey.
a.
b.
c.
d.
Emotionally Charged Questions
Limited/Biased Range of Options
Biased Order of the Questions
Subject Ignorance
Samples Provided in Class
Survey/Experiment Definitions
 Population:
Larger group you wish
to generalize your findings to … the
group your research will benefit.
 Sample of Subjects:
People you
choose from the population to survey
(study)
 Representative Sample: (noun)
Set of subjects that represent the
population (all parts …
ethnicity/sex/religion/etc.)
 Random Sampling:
(verb/procedure)
Each person in your population
has an equal chance of being
selected for your study. Ensures a
representative sample.
 Examples and Reflection Question #4
Goals Met: Describe
Definition: Behavior is studied in its natural
environment without interference from the
researcher.
Naturalistic Observation Cont.
 Advantages:
 Spontaneous
 Not a “lab” setting
 Great ideas for future
hypotheses
 Disadvantages
 Confirmation Bias

Researcher/Observer
 Hawthorne Effect
 Subject Bias
 One Chance – think
spontaneous moment!
 Reflection Question #5
Jane Goodall
60+ years of Naturalistic
Observations
Jane Goodall – chimps
and the evolutionary
value of play
 http://www.youtube.co
m/watch?v=zvpG6lkGM
Vs
Goals Met: Describe and Predict
Definition: Used to clarify the strength of a
relationship among variables.
Correlation Continued …
Examples:
What kind of correlation?
 Dark clouds and rain
 Study time and test scores
 Smoking and lifespan
 Consumption of hot cocoa
Scatter Plots and
Correlation Coefficient
 Direction
 Positive – Vary together
 Negative – Vary opposite
 None – No relationship
and outside temperature
 Strength
 -1.00 < ---0.00--- >+1.00
 +0.25
 -0.99
 +0.87
Correlation
Perfect positive
correlation (+1.00)
No relationship (0.00)
Perfect negative
correlation (-1.00)
Scatterplots, showing patterns of correlations
Correlation Continued
http://www.tylervigen.com/spurious-correlations
Advantages
Disadvantages
 Description and prediction
 Absolutely NO causality.
are possible.
 Ice Cream Sales and Murder
Rates
 Cannot explain why a relationship
exists, only that there is one.
 Illusory Correlation
(perception of correlation where
none exists)
Perceive a Patterns
 (Idaho drivers)
 Perceive a Random Event



Fail to notice a Third Variable


(shootings)
(pallegra)
No Cause/Cannot Explain
Free Response – 2015 Exam
Researchers conducted a naturalistic study of children between the ages of 5 and 7
years. The researchers visited classrooms during class party celebrations. As a
measure of hyperactivity, they recorded the number of times children left their
seats. The researchers found a strong positive correlation between sugary snacks
offered at the parties and hyperactivity. Based on these findings, the researchers
concluded that sugar causes hyperactivity.
A. How might the following explain why people may easily accept the
conclusion of the study described above?
 Confirmation bias
 Availability heuristic
 Misunderstanding of correlational studies
B. As a follow-up study, the researchers are designing an experiment to test
whether sugar causes hyperactivity. For the experiment, please do the following.
 State a possible hypothesis.
 Operationally define the dependent variable.
 Describe how random assignment can be achieved.
 Multi-Method Approach (Eclectic)
 You follow a case study closely
 You notice (as part of some naturalistic observations)
a correlation
 You survey a similar set of subjects from the population
 You find a definite mathematical correlation
 You experiment to prove cause and effect
Usually the last step in the research process.
May include other methods along the way.
Goals Met:
Explain!!
Definition:
The investigator manipulates one or more factors
called the independent variable to observe its effect on some behavior
or mental process called the dependent variable while controlling
other, relevant factors called confounding variables.
Definitions Experimentation
Independent Variable (IV):
 The controlled or manipulated variable.
The “thing” that is given or not given to
the subjects. The variable whose effect is
being studied.
Dependent Variable (DV):
 The effect (behavior or mental process)
being observed that is caused by the IV.
The variable that may change in response
to the IV.
Hypothesis and Operational Definition
(see previous)
Experimental Group (EG):
 Manipulated group
 Receives the treatment
 Receives the IV
Control Group (CG):
 Comparison Group
 Does not receive the IV
 May receive a placebo (looks like IV, but is
not have the same effect)
Experimentation Continued …
 Random Sampling
(verb)
 Get sample that represents
(noun) the population

Every KIND of person should be
represented in your sample.
 Biased Sample

Does not represent the
population/can’t generalize
 Eliminate Researcher
Bias/Subject Bias


Blind – one doesn’t know
Double-Blind – both don’t know
 Random Assignment
(another verb)
 Randomly assign
subjects to CG and EG –
to make both groups
representative.
Experimentation Continued
 Example – Reflection Sheet
Population
IV
DV
CG
EG
Experimentation Continued …
Advantages
Disadvantages
 Conclusions can be drawn
 Ethical considerations – any
about causation
 Explanations are given for
behaviors and mental
processes
 Cause and effect
time you experiment with
humans/animals
 Behavior constricted to a
laboratory (not always
natural/realistic)
 Observer Bias/Hawthorne
Effect
 Use blind/double blind
procedure to eliminate
Ethical Guidelines - APA
Informed consent
Subject can withdraw at any time
Information provided for how to contact researcher after
Confidentiality
Explain any misconceptions at the earliest possible time
(without creating bias)
6. If deception occurs, must remove misconceptions at the
end
7. Those working with animals/humans must be trained
8. Great lengths must be taken to minimize all
animal/human discomfort
1.
2.
3.
4.
5.