Chapter 1 - Thinking Critically With Psychological Science (Scientific Method)

8/6/2019 Chapter 1 - Thinking Critically With Psychological Science (Scientific Method)

http://slidepdf.com/reader/full/chapter-1-thinking-critically-with-psychological-science-scientific-method 1/52

The ScientificMethod

1



2



3

Key Issues in Human

Development1- Heredity and Environment

Heredity-oriented theories assume animportant role of underlying biologicalstructures. They point out that specificgenes may underlie development andbehavior.

Environmental explanations focus on theindividual¶s experience pertaining tothinking, health, and social factors



4

Key Issues in Human

Development� Heredity and environment interact, but

theorists still disagree over the relative

contributions of each and the manner of their interaction.

� The position that the theorists take on this

question determines the direction and

nature of their research



5

Key Issues in Human

Development2- Maturation and Learning

Maturation refers to biological processes.

Learning refers to change over time related to

practice or experience.When development is considered in terms of

maturation and learning, the emphasis is ontime.

Example: How is the biological event of menopause affected by a woman¶s lifestyle(experience)?



6

Key Issues in Human

Development3- Critical Versus Sensitive Periods

Optimal periods during which certain types of learning occur best

Readiness refers to reaching a maturational pointat which a specific behavior can be learned

Examples:

The effects of certain diseases during pregnancy

Acquiring a second language during an early ageThe critical time span several hours after birthduring which goslings become bonded to themother (imprinting)



7

The Scientific Method



8

What Makes Research Scientific?

1- Precision

2- Skepticism

3- Reliance on Empirical Evidence4- The Principle of Falsifiability

5- Openness? Replication



9

Science becomes dangerous only

when it imagines that it has

reached its goal.

(George Bernard Shaw)



10

Issues in Data Collection

1- Sampling

Random Sampling

Representative Sample

2- ReliabilityThe degree of consistency with which a

test or scale measures something.

3- Validity

The extent to which a test or scale measureswhat it is supposed to measure



11

Validity

1- Internal Validity

What happened to the experimental group

actually caused the new behavior.2- External Validity

The extent to which an experiment

corresponds to what happens in the realworld

3- Construct



12



13

How Do Psychologists Observe and

Describe Behavior?

1- Descriptive Method

2- Correlational Studies

3- Experimental Method



14

Methods of Studying Behavior

1- Descriptive Methods

Approaches that primarily involve

the observation and description of

behavior



15


2- Correlational Studies

Examine the relationship betweentwo variables to determine whether

they are associated or correlated



16


3- Experimental Methods

Approaches that go beyonddescription and attempt to

determine what causes what in

development and behavior



17

Descriptive Approaches

1- Case Studies

2- Systematic Observation

3- Questionnaires and Surveys

4- Psychological Testing

5- Developmental Research Design



18

Case Study

Sometimes are called baby biographies

They involve extensive interviews with a

particular individual or a small group of individuals

Drawbacks

1- The lack of standardization2- Reliance on language



19

Systematic Observation

Naturalistic Observation

Occurs in a natural setting

such as studying apes inthe wild or people in bars

Laboratory Observation

The psychologist has more

controlOne shortcoming is that

the presence of

researchers and special

equipment may cause

subjects to behave

differently



20

Questionnaires and Surveys

Interview that ask people directly about their

experiences, attitudes, or opinions

DrawbacksThe difficulty of getting a representative

sample

When dealing with volunteers, we may havevolunteer bias



21

Psychological Tests

Sometimes called assessment

instruments

Are procedures used for measuring andevaluating personality traits, emotional

states, aptitudes, interests, abilities, and

values



22

Psychological Testing

Objective Tests

Also called Inventories

Measure beliefs,

feelings, or behaviors

of which the individual

is awareHave more reliability

and validity

Projective Tests

Designed to tap

unconscious

feelings or motives



23



24

Projective Tests

1- Association Techniques

The Rorschach Test

TheWord Association Test2- Completion Techniques

Sentence Completion Tests

Rosenzweig Picture Frustration Study



25

The Rorschach Projective Test



26

Projective Tests

3- Construction Techniques

The Thematic Apperception Test (TAT)

The Picture Projective Test (PPT)

4- Expression Techniques

The Draw-a-person Test

The House-tree-person Test



27

Developmental Research

1- The Longitudinal Design

2- The Cross-Sectional Design

3- The Sequential-Cohort Design



28

1- The Longitudinal Design

A group of individuals is studied repeatedlyat different points in the lifespan

Drawbacks:

a. Large investments in time and money

b. Some subjects drop out or die

c. Some subjects become testwise

d. Changes in individuals may be due tothe time of measurement rather thandevelopment



29

2- The Cross-Sectional Design

Compares individuals of different ages at

one point of time

Drawbacks:a. It tells us more about age groups than

about development within the individuals

b. The cohorts differ not only inchronological age but also in the time

period in which they were born



30

3- The Sequential-Cohort Design

A mix of the two types of research

Example:

Studying a group of 4-year-olds, a group of 8-year-olds, and a group of 12-year-olds

each 2 years comparing them

longitudinally and cross-sectionally



31

The Experimental Method

in Psychology



32

Defining Psychology

Psychology is the scientific

study of behavior and mental

processes and how they areaffected by an organism¶s

physical state, mental state,and external environment.



33

Correlational Study by

Craig Anderson & Karen Dill

(2000)

The Effects of playing violentvideo games on behavior,

especially aggressive

behavior



34


Anderson and Dill (2000)

Method

A correlational study basedon questionnaires andpersonality measures

administered to a largenumber of college students



35



Results

Analysis of data indicated that

playing violent video gameswas strongly and positivelycorrelated with two factors:

a. Aggressive delinquentbehavior in real life

b. Aggressive personalitycharacteristics



36

Plausible Causes for Aggressive

Behavior



37


Behavior



38


Behavior



39

Correlational Studies

Examine the relationship between two

variables to determine whether they are

associated or correlated

Establishing a correlation between 2

variables does not indicate causality



40

Experimental Methods


The Effects of playing violent

video games on behavior,especially aggressive

behavior



41

Hypothesis

Playing violent video games

would increase aggressive

behavior



42



43



44

The Outcome of the Experiment

The results confirmed that

participants who played a

violent video game behavedmore aggressively than

participants who played a

nonviolent video game.



45




46


They tell us about cause and effect

The investigator manipulates one set of

variables (independent variables) andobserves their influence on another set of

variables (dependent variables)

To establish causality, experimenters

compare different groups, experimental

groups and control groups.



47

Experimental Design

Questions:

Who are the subjects?

What is the independent variable?

What is the variable that is going to changebecause of manipulation?

What is the dependent variable?

If there were changes in behavior, what was the

causative agent?What was the outcome of the experiment in one

sentence?



48

Ethics in Research

1- Freedom from Harm

2- Informed Consent

3- Use of Deception

4- Maintenance of Privacy



49

Understand these Terms

Hypothesis

Correlational studies

Experimental methodIndependent variable

Dependent variable

Experimental group

Control Group

Validity

Construct

Reliability

Representativesampling

Causality



50

Design Your Own Research

1- You want to examine the effect of watching

violent movies on the behavior of children, what

design are you going to use, cross-sectional,

longitudinal, or sequential-cohort design?2- What is your hypothesis?

3- How many groups are you going to have? Why?

4

- What is the population you are going toexperiment on? How are you going to select

your sample?



51

5- If you want to establish causality, whattechnique are you going to use,correlational, observational, casestudies, or experimental?

6- What is the methodology?

7- Where are you going to conduct theexperiment?

8- What are the dependent variables?

9- What are the independent variables?

10-Do you think your experiment hasinternal and external validity? Why?



52

Documents

Chapter 1 - Thinking Critically With Psychological Science (Scientific Method)