Chapter 1:
Psychology,
Research, and You
Pages 2 – 21
Food for Thought

When the city’s ice cream
sales are highest, the
number of drownings is
also highest; therefore,
increasing ice cream sales
causes an increase in
drownings.

A series of Dutch statistics
shows that an increase in
the number of storks
nesting in the area during
the spring was related to
an increase in the number
of human babies born at
that time. More storks
must mean more babies,
right?
Definitions of Psychology



The science of behavior and mental
processes
“Inner” experiences like dreams
Scientific testing and causal relationships
Becoming a Psychological Detective

What is the claim and who is making it?



Personal Bias
Evaluate authority
Cultural Bias


Whose face is on a penny?
Who stole the greatest number of bases in a
single season of professional baseball?
Becoming a Psychological Detective

Is the claim based on scientific
observations?

Does the claimant use personal experiences or
documented research?
Becoming a Psychological Detective

What do statistics reveal?

Are the test results statistically significant?
Becoming a Psychological Detective

Are there plausible alternative
explanations?

Spurious relationships


‘A’ may be related to or correlate with ‘B’, but ‘A’
does not cause ‘B’
There is another explanation
The Incredible Edible Egg


Bias? Personal gain?
Observations?


Statistics?


Most vitamins are very low in amount, less than 1%
Other explanations?


My dad says…
Good nutrition and exercise
http://youtube.com/watch?v=UmPwL1YulMA
“Trimspa, Baby”



What are they selling?
Bias?
Statistics?


Results not typical
Other explanations?


Plastic surgery
http://youtube.com/watch?v=u9oMEfFlmYQ
Review

When evaluating a claim, ask:




What is the claim and who is making it?
Is the claim based on scientific observations?
What do statistics reveal?
Are there plausible alternative explanations for
the claim?
Research Methods in Psychology

Scientific Method



Make careful and precise observations of a
phenomena or event
Develop an explanation, a theory
Develop a hypothesis


Prediction about future behaviors
Test and retest the hypothesis
Types of Research Methods





The Case Study
Naturalistic Observation
Correlational Research
Survey Research
These methods cannot give us a causeand-effect statement
Types of Research Methods
The Case Study




Also called a clinical study
In Depth
One Person or Few People
Uses data from one person to understand
the behavior in others
Types of Research Methods:
The Case Study

Advantages


Researchers can gather
a lot of detailed
information
Provides suggestions for
further research

Disadvantages

Not always
generalizable

What we learn
about one person
may not
necessarily apply
to others
Types of Research Methods
Naturalistic Observation



Describes the settings, frequency, and
characteristics of certain behaviors in the
real world
Observe in natural settings
Experimenter does not interfere at all
Types of Research Methods
Naturalistic Observation

Advantage

Real life situation data
instead of generalized or
simulated

Disadvantage

Reactive Observations

Ones that interfere
with the behavior
being studied
Types of Research Methods
Correlational Research




Test of whether two items are related or
tend to occur together
Example: SAT/ACT Exam scores and Firstyear GPA
Shown as a correlation coefficient (r)
Direction refers to Positive or Negative
Correlations
100
90
80
70
60
50
40
30
20
10
0
100
90
80
70
60
50
40
30
20
10
0
1
2
3
4
Negative Correlation
x↓,y↑
OR
5
- 1.00
x↑,y↓
1
2
3
Positive Correlation
x↑,y↑
OR
4
5
+ 1.00
x↓,y↓
Correlations:
1.
2.
3.
4.
Studying time and
grades
Time spent reading
and weight lost
Cost of a diamond
and number of carats
Time spent eating
and weight lost
a.
+0.90
b.
-0.08
c.
+0.70
d.
-0.90
Types of Research Methods
Survey Research






Gathers data from a sample that represents
a larger population
Efficient way to collect lots of information
Face-to-Face interviews
Telephone
Written
Computer
Types of Research Methods
Survey Research

Must find a representative sample



Reflects the larger population
Questions must elicit meaningful and useful
responses
Must check questions for cultural and personal
bias
Types of Research Methods
The Experimental Method



Can provide cause-and-effect statements
Involves manipulating variables to
determine how they affect other variables
Considered most powerful research
method
Types of Research Methods
The Experimental Method

Independent variable (usually x)


Variable manipulated to see effects on the
dependent variable
Dependent variable (usually y)

Variable that shows the test results by reacting to
the independent variable
The Experimental Method

Operational definitions


Experimental group


Precise definition that helps others replicate the
experiment
Participants exposed to the independent variable
Control group

Participants not exposed to the independent
variable
The Experimental Method

To insure reliability:


Repeat the research
Control extraneous variables


Ones other than the independent variable that can
influence the outcome of the experiment
Select very similar control and experimental
groups

Random assignment – based on chance
Statistics and Psychology

Statistics


Used to summarize, analyze, and interpret data
Descriptive and Inferential Statistics
Descriptive vs. Inferential


Summarizes a set of
numbers
Measure of central
tendency




Mean
Mode
Median
Measures of variability


Range
Standard Deviation


Determines if ind.
variable had a
significant effect
Mathematical odds of
of the observed
behavior

Does it happen by
chance?
Research Ethics




Protection from harm
Confidentiality
Voluntary Participation
Deception and Intimidation

Debriefing

Researchers must explain any deception at the
conclusion of the experiment
The End