1. Research Methods and Critical Thinking
Chapter 2
Research Methods and Critical Thinking

2. Key Questions Why is the scientific method important to psychologists?
How do psychologists collect information?
How is an experiment performed?
What other research methods do psychologists use?
How dependable is psychological information found in the popular press?
What ethical questions does psychological research raise?

3. Key Terms Scientific method Anthropomorphic Double-blind experiment
Dependent variable
Observation
Observational record
Extraneous variable
Experimenter effect
Hypothesis
Correlated
Experimental group
Case study
Operation
Correlational study
Control group
Natural clinical tests
Theory
Coefficient of correlation
Random assignment
Self-fulfilling prophecy
Falsifiable
Field experiment
Frontal lobotomy
Positive correlation
Naturalistic observation
Statistically significant
Negative correlation
Replicate
Representative sample
Correlation method
Causation
Parascience
Population
Experimental method
Linear relationships
Placebo
Biased sample
Clinical method
Curvilinear
Placebo effect
Courtesy bias
Survey method
Experiment
Endorphins
Natural setting
Subjects
Single-blind experiment
Observer effect
Variable
Observer bias
Independent variable

4. The Scientific Method
Observation: Carefully recording facts and events
Six Basic Elements
Observation
Defining a problem
Proposing a hypothesis (an educated guess that can be tested)
Gathering evidence/testing the hypothesis
Publishing results
Building a theory

5. Hypothesis
Hypothesis: Tentative explanation of an event or relationship
Testable hunch or education guess about behavior

6. Puzzled?
Operational definition activity

7. Operational Definitions
Handout

8. Operational Definition
Operation Definition: States the exact procedures used to represent a concept
Allow abstract ideas to be tested in real-world terms
See page 29 FIGURE 2-1

9. Cleve Hans
The Wonder Horse! Clever Hans seemed to solve difficult math problems, which he answered by tapping his foot. If you asked Hans, “What is 12 times 2, minus 18”, Hans would tap his foot six times. Hans was so astonishing that an inquiring scientist decided to discover if Hans actually did arithmetic.
How does Hans really do the trick

10. Can A Horse Add?

11. Well…can it?
Your investigation of Hans’ math skills would probably begin with careful observation of both horse and owner while Hans was performing. Assume that these observations fail to reveal any obvious cheating.
Then the problem becomes more clearly defined: What signals Hans to start and stop tapping his foot? Your first hypothesis might be that the owner is giving Hans a signal. Your proposed test would be to make the owner leave the room. Then someone else could ask questions.
You test would either confirm or deny the owner’s role. This evidence would support or eliminate the cheating hypothesis. By changing the conditions under which you observe Hans, you have controlled the situation to gain more information from your observations.

12. Yes…and No
Hans could still answer when his owner was out of the room. But a brilliant series of controlled observations revealed Hans’ secret.
If Hans couldn’t see the questioner, he could answer. It seems that questioners always lowered their heads (to look at Hans’ cue to start tapping. When Hans had tapped the correct number, a questioner would always look up to see if Hans was going to stop
This was Hans’ cue to stop tapping!

13. Scientific Theory
Theory: Interrelates concepts and facts in a way that summarizes a large number of observations
A system of ideas that interrelates facts and concepts, summarizes existing data, and predicts future observations
A good theory must be falsifiable; i.e., operationally defined so that it can be disconfirmed

14. GATHER EVIDENCE & TEST HYPOTHESIS REJECT OR RETAIN HYPOTHESIS
Theory Building
OBSERVATION
DEFINE PROBLEM
PROPOSE HYPOTHESIS
GATHER EVIDENCE & TEST HYPOTHESIS
REJECT OR RETAIN HYPOTHESIS
PUBLISH RESULTS
THEORY BUILDING
Psychologists use the logic of science to answer questions about behavior. Specific hypotheses can be tested in a variety of ways, including naturalistic observation, correlational studies, controlled experiments, clinical studies, and the survey method. Psychologists revise their theories to reflect the evidence they gather. New or revised theories then lead to new observations. Problems, and hypotheses

15. Research Methods Experimental Method:
Controlled experimentations using the correlation method
To identify cause-and-effect relationships, we conduct experiments
Directly vary a condition you might think affects behavior
Create two or more groups of subjects, alike in all ways except the condition you are varying
Record whether varying the condition has any effect on behavior
Questionnaires, surveys, and polls

16. Research Methods
Naturalistic Observation: Observing a person or an animal in their natural setting in which they/it live(s)
Problems
Observer Effect: Changes in behavior caused by an awareness of a person or animal being observed
Observer Bias: Occurs when observers see what they expect to see or record only selected details
Anthropomorphic Fallacy: Attributing human thoughts, feelings, or motives to animals, especially as a way of explaining their behavior

17. Research Method worksheet
Worksheet do as a class

18. Naturalistic Observation
Jane Goodall’s naturalistic observation

19. Correlations and Relationships
Research Methods
Correlations and Relationships
Correlational Methods: Find existence of a consistent, systematic relationship between two events, measures, or variables
Correlation Coefficient: Statistic ranging from –1.00 to +1.00; the sign indicates the direction of the relationship

20. Research Methods Correlations in psychology are rarely perfect
Closer the statistic is to –1.00 or to +1.00, the stronger the relationship
Correlation of 0.00 demonstrates no relationship between the variables
EX: Identical twins tends to have almost identical IQs. In contrast, the IQs of parents and their children are only generally similar.
The correlation between the IQs and parents and children is .35; between identical twins its .86.

21. Correlations and Relationships (cont.)
Research Methods
Correlations and Relationships (cont.)
Positive Correlation: Increases in one variable are matched by increases in the other variable
Negative Correlation: Increases in one variable are matched by decreases in the other variable
Correlation does not demonstrate causation: Just because two variables are related does NOT mean that one variable causes the other to occur
Causation: A cause-and-effect connection)

22. Fig. 1.7 The correlation coefficient tells how strongly two measures are related. These graphs show a range of relationships between two measures, A and B. If a correlation is negative, increases in one measure are associated with decreases in the other. (As B gets larger, A gets smaller.) In a positive correlation, increases in one measure are associated with increases in the other. (As B gets larger, A gets larger.) The center-left graph (“medium negative relationship”) might result from comparing anxiety level (B) with test scores (A): Higher anxiety is associated with lower scores. The center graph (“no relationship”) would result from plotting a person’s shoe size (B) and his or her IQ (A). The center-right graph (“medium positive relationship”) could be a plot of grades in high school (B) and grades in college (A) for a group of students: Higher grades in high school are associated with higher grades in college.

23. Fig. 1.9 The relationship between years of college completed and personal income (hypothetical data).

24. Correlation Worksheet

25. How to Conduct an Experiment
Experiment: A formal trial undertaken to confirm or disconfirm a hypothesis.
To perform an experiment you would do the following:
Directly vary a condition you think might affect behavior
Create two or more groups of subjects. These groups should be alike in all ways except the condition you are varying
Record whether varying the condition has any effect on behavior

26. Variables
Definition: Any condition that can change, and might affect, experiment's outcome
Independent Variable: Condition(s) altered by the experimenter; experimenter sets their size, amount, or value; these are suspected causes for behavioral differences
Dependent Variable: Demonstrates effects that independent variables have on behavior
Extraneous Variables: Conditions that a researcher wants to prevent from affecting the outcomes of the experiment (e.g., number of hours slept before the experiment)

27. Identifying variables
Worksheet
Worksheet Simpsons

28. Groups
Experimental Group: The group of subjects that gets the independent variable
Control Group: The group of subjects that gets all conditions EXCEPT the independent variable
Random Assignment: Subject has an equal chance of being in either the experimental or control group

32. Evaluating Experiments’ Results
Statistically Significant: Results gained would occur very rarely by chance alone
Meta-analysis: Study of results of other studies

33. Placebo Effects Placebo: A fake pill (sugar) or injection (saline)
Placebo Effect: Changes in behavior that result from belief that one has ingested a drug
Placebos alter our expectations about our own emotional and physical reactions
These expectancies then influence bodily activities
Relieve pain by getting pituitary to release endorphins
Also gain some effect through learning

34. Controlling Placebo Effects
Single Blind Experiment: Only the subjects have no idea whether they get real treatment or placebo
Double Blind Experiment: The subjects AND the experimenters have no idea whether the subjects get real treatment or placebo
Best type of experiment if properly set up
Herbal remedies may be based on placebo effect

35. Experimenter Effects
Definition: Changes in behavior caused by the unintended influence of the experimenter
Self-Fulfilling Prophecy: A prediction that leads people to act in ways to make the prediction come true

36. The Clinical Method
Case Study: In-depth focus on all aspects of a single case
Natural Clinical Tests: Natural events, such as accidents, that provide psychological data
Survey Method: Using public polling techniques to answer psychological questions

37. Phineas Gage
Video
Within 2 months Phineas Gage could walk, talk, and move about normally. Injury forced his personality to change
Instead of the honest and dependable worker he had been before, Gage became a surly, foul-mouthed liar.
FRONTAL LOBOTOMY (One Flew Over the Cuckoo’s Nest)

38. Table 1.5 – Comparison of Psychological Research Methods

39. Sampling
Representative Sample: Small group that accurately reflects a larger population
Population: Entire group of animals or people belonging to a particular category (e.g., all married women)
Internet Surveys: Web based research; low cost and can reach many people
Courtesy Bias: Problem in research; a tendency to give “polite” or socially desirable answers
Samples are not representative

40. Separating Fact from Fiction (Are the Stories in the National Enquirer True?)
Be skeptical
Consider the source of information
Ask yourself, “Was there a control group?”
Look for errors in distinguishing between correlation and causation (are claims based on correlational results yet passed off as causations?)

41. Separating Fact from Fiction
Be sure to distinguish between observation and inference Beware of oversimplifications, especially those motivated by monetary reasons
Single examples are not proof!

42. Ethical Guidelines for Psychological Research
Do no harm
Accurately describe risk to potential subjects
Ensure that participation is voluntary
Minimize any discomfort to participants
Maintain confidentiality

43. Ethical Guidelines for Psychological Research (cont.)
Do not unnecessarily invade privacy
Use deception only when absolutely necessary
Remove any misconceptions caused by deception (debrief)
Provide results and interpretation to participants
Treat participants with dignity and respect