PSYCHOLOGICAL RESEARCH

DESIGN & METHODS

AP PSYCHOLOGY: CHAPTER 2

Bellwork: Why do we need

Psychological Research?

What were your thoughts..

Hindsight Bias

“I knew it all along”

phenomenon

Examples..

2 groups.. Absence

makes the heart

grow fonder or..

Weakens..

Flashcards..

Overconfidence

We tend to think we know more

than we do..

WREAT WATER

ETRYN ENTRY

GRABE BARGE

OCHSA

Overconfidence In history…

“We don’t like their sound. Groups of guitars are on their way out.” –

Decca Records in turning down a contract w the Beatles.

“They couldn’t hit an elephant at this distance.” General Sedgwick

just before being killed during a Civil War battle 1864;

Given random data, we look for order and meaningful patterns.

Order in Random Events

Your chances of being dealt either of these hands is precisely the same: 1 in 2,598,960.

Order in Random Events

Given large numbers of random outcomes, a few are likely to express order.

Angelo and Maria Gallina won two California lottery

games on the same day.

Many people have been struck by

lightening 2+ times.

Think about it! An event

happens to 1 in a billion

people occurs 7 times a day, 2500 times a

year!

The Research Process (Big Picture)

The Research Process (The Detailed Picture)

Components of Research

Variables

• Factors or characteristics in research.

• Can be manipulated or measured.

Data

• # representing research findings

• Provide the basis for research conclusions.

Theory

• Statements that can account for, or predict behavior.

• Subject to critical thinking.

Components of Research

Critical Thinking

• Basis for research (stems from curiosity).

• Helps assess reliability & claims.

Hypothesis

• Testable prediction.

Operational Definition

• Descriptions of the EXACT operations or methods.

• Operational Definition Exercise

Research Methods

Goals

Describebehavior

Accurately predict

behavior

Demonstrate control over

Behavior

Explain how & why

behavior occurs.

Naturalistic Observation

Case Studies

Surveys

Correlational Studies

*Helps measure behavior

Experiments

*Helps determine cause & effect

Methods of Psychological Research (p. 44)

Method Features Strengths Weaknesses

Naturalistic

Observation

Observation of human or

animal behavior in the

environment it typically

occurs.

Provides descriptive data

about behavior presumably

uncontaminated by outside

influences.

Observer bias and

participant self-consciousness

can distort results.

Case Studies Intensive examination of the

behavior and mental

processes associated with a

specific person or situation.

Provide detailed descriptive

analysis of new, complex, or

rare phenomena.

May not provide

representative picture of

phenomena.

Surveys Standard sets of questions

asked of a large number of

participants.

Gather large amounts of

descriptive data relatively

quickly and inexpensively.

Sampling errors, poorly

phrased questions, and

response biases can distort

results.

Correlational

Studies

Examine relationships

between research

variables

Can test predictions,

evaluate theories, and

suggest new hypotheses.

Cannot confirm causal

relationships between

variables.

Methods of Psychological Research (p. 44)

Method Features Strengths Weaknesses

Experiment Manipulation of an

independent variable

and measurement of its

effects on a dependent

variable.

Can establish a cause-

effect relationship

between independent

and dependent variables.

Confounding variables

may prevent valid

conclusions.

Which Method to Use?

Identify parenting styles commonly used in the United States

Determine why a school failed to meet

appropriate standards.

Describe differences in gender communication

among 5 year old children.

Determine a relationship between

violent media (TV, video games, etc) and aggressive behavior.

Identify the capacity of human short term

memory.

Selecting Participants for Research

Random Sample

Participants selected from the population (whose members had an equal chance of being selected).

Attempts to avoid biased sampling.

Representative Sample

The sample of participants accurately reflect the greater population.

Attempt to represent as many characteristics as possible (age/gender, etc).

Population Sampling

Process of selecting participants who are members of the population.

Using the sample, researchers use generalizability to draw conclusions.

Selecting Participants for Research

Random

Sampling

Representative

Sample

Leads to…

Sampling Error

• Those selected may be slightly different than those not selected

Non Response Error

• Participants selected may not agree to participate.

Cost/Budget Issues

• Convenience Samples

• Drawing participants from conveniently available populations.

Population: Class of 1941

Random Selection of Subjects

Provides a Representative Sample of the Class of 1941

Experimental Group Control Group

Random

Assignment

of Subjects –

Makes

subjects in

both groups

equal:

controls for

subject

differences

Example:

•Can eye movements cause a change in emotion?

•Does Shapiro’s EMDR (eye movement desensitization and reprocessing) technique reduce anxiety?

•EMDR treatment causes a significant reduction in anxiety.

Experimental Method

Experimental Variables

Independent Variable

(IV)

Factor or condition being manipulated by experimenter.

EMDR

Dependent Variable

(DV)

Factor being measured.

Anxiety

Independent vs Dependent

1. Developmental psychologists want to know if exposing children to public television improves their reading skills.

2. Physiological psychologists wonder about the relationship between the intake of wine and emotional reactions to frightening stimuli.

3. Sensory psychologists want to know whether birds also experience visual illusions.

4. Operant psychologists want to know whether reinforcing (rewarding) comments will make people work harder on an assembly line.

5. Cognitive psychologists wonder what kind of diagrams are easiest for people to remember.

6. Comparative psychologist study whether a young monkey will prefer to spend time with a pretend monkey

7. made of wire that also provides milk or a pretend monkey that is covered with cloth but provides no milk.

8. A clinical psychologist wants to know whether people who have had psychotherapy are more or less likely to have problems in the future.

9. A social psychologist wants to know whether being polite or rude to people tends to make them more cooperative.

10. An organizational psychologist test to see if wearing name tags make the employees happier with their work.

11. A personality psychologist explores whether extroverted people have more fun at parties.

Experimental Subject Groups

Experimental Group

Exposed to the IV

Participants who receive

EMDR treatment

Control Group

Not exposed to the IV

Serves as a basis for

comparison

Participants who did not

receive EMDR treatment

ALL OTHER

CONDITIONS MUST

BE EQUAL! Why?

Confounding Variables

Factor that affects the DV (along with

or instead of the IV)

E Group: 50 min. focus on memory

C Group: 8 min.

Focus on memory

Experimental Controls

Control: Random Assignment

Random variables are evenly distributed.

Participants are distributed through a random process (computer

distribution, coin flip, etc).

Random Variables

Uncontrolled (or uncontrollable) that effect the DV.

Personality, background, life experiences, etc.

Experimental Controls

Experimenter Bias

Type of confounding variable

Unintentionally encourage participant responses to support hypothesis

Control: Double Blind Study (design in which experimenter nor participants

know who is a part of experimental or control groups

Participant Bias

Knowledge/expectation of treatment changes the participants

behavior/results.Control: Placebo Treatment

100 Depressed Subjects

50 - Drug

50 - No Drug

38 Improve

8 Improve

100 Depressed Subjects

50 - Drug

50 - Placebo

38 Improve

20 Improve

Placebo Effect