1. INTRODUCTION TO RESEARCH
PSYCHOLOGY AS A SCIENCE

2. The Study of Psychology
Psychology is the scientific study of behavior and mental processes
Psychology values empirical evidence
Psychology employs critical thinking
Psychology employs systematic research methods
© John Wiley & Sons, Inc.
Huffman: PSYCHOLOGY IN ACTION, 7E

3. ALWAYS QUESTION THE ANSWERS
Critical Thinking
thinking that does not blindly accept arguments and conclusions
examines assumptions
discerns hidden values
evaluates evidence
The Amazing Randi--Skeptic

4. Barriers to Critical Thinking
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
False Consensus Effect
tendency to overestimate the extent to which others share our beliefs and behaviors

5. The Need for Psychological Science: Psychologists, like all scientists, use the scientific method

6. PSYCHOLOGY AND THE SCIENTIFIC METHOD
Theory
an explanation using an integrated set of principles that organizes and predicts observations
Hypothesis
a testable prediction
often implied by a theory

7. 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

8. You Want to Study Something? Make it SPECIFIC and MEASURABLE!
Operational Definition
a statement of procedures (operations) used to define research variables
a measureable description of a construct
Example-
intelligence may be operationally defined as what an intelligence test measures (IQ score)

9. Operational Definitions
Operationalize the following constructs:
Age
Weight
Academic performance
Happiness
Relationship with parents

10. Descriptive Study Describes a set of facts
Does not look for relationships between facts
Does not predict what may influence the facts
May or may not include numerical data
Example: measure the % of new students from out-of-state each year since 1980

11. Descriptive Design
Naturalistic Observation
observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation

12. 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?

13. Data Collection: Surveys
Surveys are instruments designed to sample attitudes or behaviors
technique for ascertaining the self-reported attitudes or behaviors of people
usually by questioning a representative, random sample of people
Example: asking persons at a rally how they feel about animal rights issues

14. Population/Sample
Population: The large group being studied (ex: American teenagers)
Sample: The smaller group drawn from the population (ex: 1000 teenagers from 9 urban and rural cities)

15. POPULATION/SAMPLE WHO DO YOU WANT TO STUDY?
Create three examples of population.
HOW WOULD YOU STUDY EACH?
Create examples of samples for each.

16. Psychological Research
WHERE? Setting - field vs. laboratory
WHO? Population/Sample
WHAT? Research design
descriptive, correlational, or experimental
HOW? Data collection: self-report vs. observational
Identify the appropriate setting, design, and data collections for:
Teenagers’ interactive patterns
The effects of a new drug for depression
The connection between marriage and happiness

17. Research Design #2: Correlation
Collects a set of facts organized into two or more categories
measure parents’ disciplinary style
measure children’s behavior
Examine the relationship between categories
Correlation reveals relationships among facts
The higher the discipline rates among parents, the lower the behavioral problems by their children

18. Height and Temperament of 20 Men
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 68 90 42 81 39 48 72 57 30 84
Subject
Height in
Inches
Temperament

19. Scatterplot of Height and Temperament
Correlation 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25
Temperament
scores
Height in inches
Scatterplot of Height and Temperament

20. Correlation: Scatterplots
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

21. Scatterplots, showing patterns of correlations
Perfect positive
correlation (+1.00)
No relationship (0.00)
Perfect negative
correlation (-1.00)
Scatterplots, showing patterns of correlations

22. Correlational Research
The correlation technique indicates the degree of association between 2 variables
Correlations vary in direction:
Positive association: increases in the value of variable 1 are associated with increases in the value of variable 2
Negative association: increases in the value of variable 1 are associated with decreases in the value of variable 2
No relation: values of variable 1 are not related to variable 2 values

23. (positive or negative)
Correlation
Correlation Coefficient
a statistical measure of the extent to which two factors vary together, and thus how well either factor predicts the other
Indicates direction
of relationship
(positive or negative)
Correlation
coefficient
r = +.37
Indicates strength
of relationship
(0.00 to 1.00)

24. Correlational Design: Limitations
Correlation cannot prove causation
Do democratic parents produce better behaved children?
Do better behaved children encourage parents to be democratic?
May be an unmeasured common factor
e.g., good neighborhoods produce democratic adults and well behaved children

25. Correlation: Is there a relationship between self-esteem and depression?
Three Possible Cause-Effect Relationships
could cause
(1)
Low self-esteem
Depression or
(2)
Depression
could cause
Low self-esteem or
Low self-esteem
(3)
Distressing events
or biological
predisposition
could cause
and
Depression

26. Types of Research Design
Descriptive
Describes
Correlational
Establishes Relationship
Experimental
Attempts to establish causation

27. Differentiating Research Methods