+

Chapter 2 Research Methods and

Critical Thinking

+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?

+ Key Terms

+The Scientific Method

Observation: Carefully recording facts and events

Six Basic Elements1. Observation

2. Defining a problem

3. Proposing a hypothesis (an educated guess that can be tested)

4. Gathering evidence/testing the hypothesis

5. Publishing results

6. Building a theory

+Hypothesis

Hypothesis: Tentative explanation of an event or relationship

Testable hunch or education guess about behavior

+Puzzled?

Operational definition activity

+Operational Definitions

Handout

+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

+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

+Can A Horse Add?

+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.

+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!

+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

+Theory Building

+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

+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

+Research Method worksheet

Worksheet do as a class

+Naturalistic Observation

Jane Goodall’s naturalistic observation

+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

+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.

+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)

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.

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

+

Correlation Worksheet

+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:

1. Directly vary a condition you think might affect behavior

1. Create two or more groups of subjects. These groups should be alike in all ways except the condition you are varying

1. Record whether varying the condition has any effect on behavior

+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)

+Identifying variables

Worksheet

Worksheet Simpsons

+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

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+

+Evaluating Experiments’ Results

Statistically Significant: Results gained would occur very rarely by chance alone

Meta-analysis: Study of results of other studies

+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

+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

+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

+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

+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)

+Table 1.5 – Comparison of Psychological Research Methods

+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

+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?)

+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!

+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

+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