1. Myers’ PSYCHOLOGY (7th Ed)
Chapter 1
Thinking Critically with Psychological Science
James A. McCubbin, PhD
Clemson University
Worth Publishers

2. The Need for Psychological Science
Psychologists, like all scientists, use the scientific method to construct theories that organize observations and imply testable hypotheses

3. 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

4. The Need for Psychological Science
Critical Thinking
thinking that does not blindly accept arguments and conclusions
examines assumptions
discerns hidden values
evaluates evidence
The Amazing Randi--Skeptic

5. 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

6. The Need for Psychological Science

7. 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

8. 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

9. Description
Psychologists describe behavior using case studies, surveys, and naturalistic observation

10. 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?

11. Description Survey Random Sample
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

12. Description False Consensus Effect Population
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

13. Description

14. Description Naturalistic Observation
observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation

15. (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)

16. 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

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

18. 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

19. Experimentation Placebo Double-blind Procedure
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

20. Experimentation Experimental Condition Control 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

21. Experimentation Random Assignment
assigning participants to experimental and control conditions by chance
minimizes pre-existing differences between those assigned to the different groups

22. Experimentation Independent Variable Dependent 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

23. Experimentation

24. 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

25. Statistical Reasoning
A Skewed Distribution 90
475
710 70
Mode Median Mean
One Family
Income per family in thousands of dollars

26. 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

27. Frequently Asked Questions about Psychology
Can laboratory experiments illuminate everyday life?

28. 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

29. Frequently Asked Questions about Psychology
Does behavior vary with gender?

30. Frequently Asked Questions about Psychology
Why do psychologists study animals?
Is it ethical to experiment on animals?
Is it ethical to experiment on people?

31. Frequently Asked Questions about Psychology
Is psychology free of value judgments?

32. Frequently Asked Questions about Psychology
Is psychology potentially dangerous?