myers7e enhanced 01
TRANSCRIPT
Myers’ PSYCHOLOGY(7th Ed)
Chapter 1
Thinking Critically with Psychological Science
James A. McCubbin, PhD
Clemson University
Worth Publishers
The Need for
Psychological Science
Psychologists, like all scientists, use the scientific method to construct
theories that organize observations and imply testable hypotheses
The Need for
Psychological Science
Hindsight Bias
we tend to believe, after learning an outcome, that we would have foreseen it
the “I-knew-it-all-along” phenomenon
Overconfidence
we tend to think we know more than we do
The Need for
Psychological Science
Critical Thinking
thinking that does not blindly accept arguments and conclusions
examines assumptions
discerns hidden values
evaluates evidenceThe Amazing Randi--Skeptic
The Need for
Psychological Science
Theory
an explanation using an integrated set of principles that organizes and predicts observations
Hypothesis
a testable prediction
often implied by a theory
The Need for
Psychological Science
The Need for
Psychological Science
Operational Definition
a statement of procedures (operations) used to define research variables
Example-
intelligence may be operationally defined as what an intelligence test measures
The Need for
Psychological Science
Replication
repeating the essence of a research study to see whether the basic finding generalizes to other participants and circumstances
usually with different participants in different situations
Description
Psychologists describe behavior using case studies, surveys, and
naturalistic observation
Description
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?
Description
Survey
technique for ascertaining the self-reported attitudes 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 inclusion
Description
False Consensus Effect
tendency to overestimate the extent to which others share our beliefs and behaviors
Population
all the cases in a group, from which samples may be drawn for a study
Description
Description
If marbles of two colors are mixed well in the large jar, the fastest way to know their ratio is to blindly transfer a few into a smaller one and count them
Description
Naturalistic Observation
observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation
Correlation
Correlation Coefficient a statistical measure of the extent to which two factors vary
together, and thus how well either factor predicts the other
Correlation
coefficient
Indicates direction
of relationship
(positive or negative)
Indicates strength
of relationship
(0.00 to 1.00)
r = +.37
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
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
Correlation
Height and Temperament of 20 Men
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
80
63
61
79
74
69
62
75
77
60
64
76
71
66
73
70
63
71
68
70
75
66
60
90
60
42
42
60
81
39
48
69
72
57
63
75
30
57
84
39
SubjectHeight in
InchesTemperament Subject
Height in
InchesTemperament
Correlation
Scatterplot of Height and Temperament
55 60 65 70 75 80 85
959085807570656055504540353025
Temperament
scores
Height in inches
Correlation
Three Possible Cause-Effect Relationships(1)
Low self-esteemDepression
(2)Depression
Low self-esteem
Low self-esteem
Depression
(3)Distressing events
or biologicalpredisposition
could cause
could cause
could cause
or
or
and
Illusory Correlation
Illusory Correlation the perception
of a relationship where none exists
Conceive Do not conceive
Adopt
Do not
adopt
disconfirming
evidence
confirming
evidence
disconfirming
evidence
confirming
evidence
Two Random
Sequences
Your chances of being dealt either of these hands is precisely the same: 1 in 2,598,960.
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
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
Experimentation
Experimental Condition
the condition of an experiment that exposes participants to the treatment, that is, to one version of the independent variable
Control Condition
the condition of an experiment that contrasts with the experimental treatment
serves as a comparison for evaluating the effect of the treatment
Experimentation
Random Assignment
assigning participants to experimental and control conditions by chance
minimizes pre-existing differences between those assigned to the different groups
Experimentation
Independent Variable
the experimental factor that is manipulated
the variable whose effect is being studied
Dependent Variable
the experimental factor that may change in response to manipulations of the independent variable
in psychology it is usually a behavior or mental process
Experimentation
Research Strategies
Design of the subliminal tapes experiment
Subliminal tape content
Self-esteem Memory
Memory
Self-esteem
Tape label
Statistical Reasoning
Our Brand Brand Brand
Brand X Y Z
100%
99
98
97
96
95
Percentage
still functioning
after 10 years
Brand of truck
Statistical Reasoning
Our Brand Brand Brand
Brand X Y Z
100%
90
80
70
60
50
40
30
20
10
0
Percentage
still functioning
after 10 years
Brand of truck
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
Statistical Reasoning
A Skewed Distribution
15 20 25 30 35 40 45 50 90 475 710
70
Mode Median Mean
One Family Income per family in thousands of dollars
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
Frequently Asked Questions
about Psychology
Can laboratory experiments illuminate everyday life?
Frequently Asked Questions
about Psychology
Does behavior depend on ones culture? Culture--the enduring behaviors,
ideas, attitudes, and traditions shared by a large group of people and transmitted from one generation to the next
Frequently Asked Questions
about Psychology
Does behavior vary with gender?
Frequently Asked Questions
about Psychology
Why do psychologists study animals?
Is it ethical to experiment on animals?
Is it ethical to experiment on people?
Frequently Asked Questions
about Psychology
Is
psychology free of value judgments?
Frequently Asked Questions
about Psychology
Is psychology potentially dangerous?