11

Developed by Joseph A. Davis, Ph.D.Developed by Joseph A. Davis, Ph.D.

Abnormal Psychology Ninth Edition 9/eAbnormal Psychology Ninth Edition 9/e

McGraw-Hill Copyright © 2005. This McGraw-Hill multimedia product and its contents are protected under copyright law.  The following are prohibited by law: any public performance or display, including transmission over any network; preparation of any derivative work, including the extraction, in whole or part, of any images; any rental, lease, or lending of the program.

McGraw-Hill Copyright © 2005. This McGraw-Hill multimedia product and its contents are protected under copyright law.  The following are prohibited by law: any public performance or display, including transmission over any network; preparation of any derivative work, including the extraction, in whole or part, of any images; any rental, lease, or lending of the program.

A PowerPoint™ Slide Presentation forA PowerPoint™ Slide Presentation for

Lauren B. Alloy, Ph.D.John H. Riskind, Ph.D.Margaret B. Manos

Lauren B. Alloy, Ph.D.John H. Riskind, Ph.D.Margaret B. Manos

22

Chapter 3Chapter 3

Research Methods in Abnormal PsychologyResearch Methods in Abnormal Psychology

33

Chapter Main PointsChapter Main Points

Characteristics of the Scientific Method Research Designs

Characteristics of the Scientific Method Research Designs

44

Characteristics: Scientific MethodCharacteristics: Scientific Method

55

Characteristics: Scientific MethodCharacteristics: Scientific Method

Skeptical Attitude Objectives:

Description Prediction Control Understanding

Skeptical Attitude Objectives:

Description Prediction Control Understanding

66

Characteristics: Scientific Method Characteristics: Scientific Method

Internal Validity: Confounding Variables:

occurs when two or more causal factors are exerting an effect on the same thing at the same time, thus interfering with accurate measurement of the causal role of either one

Internal Validity: Confounding Variables:

occurs when two or more causal factors are exerting an effect on the same thing at the same time, thus interfering with accurate measurement of the causal role of either one

77

Characteristics: Scientific MethodCharacteristics: Scientific Method

External Validity: Generalizability:

A research finding’s ability to be applied to difference populations, settings and conditions

Representativeness Sample: Degree to which the sample’s essential

characteristics match those of the populations we want to generalize about

External Validity: Generalizability:

A research finding’s ability to be applied to difference populations, settings and conditions

Representativeness Sample: Degree to which the sample’s essential

characteristics match those of the populations we want to generalize about

88

Characteristics: Scientific MethodCharacteristics: Scientific Method

Scientific Procedures: The Hypothesis:

A tentative explanation for behavior Operational Definitions:

Defined in terms of operations that can be observed and measured

Scientific Procedures: The Hypothesis:

A tentative explanation for behavior Operational Definitions:

Defined in terms of operations that can be observed and measured

99

Characteristics: Scientific MethodCharacteristics: Scientific Method

Methods of Control: Independent Variable:

A factor that is manipulated by the experimenters in an effort to measure its effects

Dependent Variable: A factor that will presumably be affected by the

manipulation of the independent variable and whose changes the experiment aims to measure

Methods of Control: Independent Variable:

A factor that is manipulated by the experimenters in an effort to measure its effects

Dependent Variable: A factor that will presumably be affected by the

manipulation of the independent variable and whose changes the experiment aims to measure

1010

Characteristics: Scientific MethodCharacteristics: Scientific Method

Methods of Control: Experimental Condition:

A condition in which the treatment is present Control Condition:

A condition in which the treatment is absent Random Assignment:

Assigning subjects randomly to the different groups in the experiment

Methods of Control: Experimental Condition:

A condition in which the treatment is present Control Condition:

A condition in which the treatment is absent Random Assignment:

Assigning subjects randomly to the different groups in the experiment

1111

Characteristics: Scientific MethodCharacteristics: Scientific Method

Minimizing the Expectation Effect: Demand Characteristics:

Subjects respond according to an experimenter’s expectations

Experimenter Effects: Knowledge of an experimental condition that can

bias an experimenter’s observations of behavioral results

Minimizing the Expectation Effect: Demand Characteristics:

Subjects respond according to an experimenter’s expectations

Experimenter Effects: Knowledge of an experimental condition that can

bias an experimenter’s observations of behavioral results

1212

Characteristics: Scientific MethodCharacteristics: Scientific Method

Minimizing the Effects of Expectations: Placebo Effect:

A substance that looks like a drug or other active substance but is actually an inert, or inactive, substance

Double-blind Procedure: Both the subject and the experimenter are kept

unaware as to which treatment is being administered

Minimizing the Effects of Expectations: Placebo Effect:

A substance that looks like a drug or other active substance but is actually an inert, or inactive, substance

Double-blind Procedure: Both the subject and the experimenter are kept

unaware as to which treatment is being administered

1313

Characteristics: Scientific MethodCharacteristics: Scientific Method

Statistical Inference: The Null Hypothesis:

The assumption that the independent variable has had no effect on the study or experiment

Clinical Significance: Can the clinical findings be of any real help in

treatment?

Statistical Inference: The Null Hypothesis:

The assumption that the independent variable has had no effect on the study or experiment

Clinical Significance: Can the clinical findings be of any real help in

treatment?

1414

Correlational ResearchCorrelational Research

Case-control Design: People diagnosed as having a particular

mental disorder are compared with controls Longitudinal Studies:

Behaviors of the same subject over an extended period of time

High-risk design

Case-control Design: People diagnosed as having a particular

mental disorder are compared with controls Longitudinal Studies:

Behaviors of the same subject over an extended period of time

High-risk design

1515

Epidemiological StudiesEpidemiological Studies

Incidence: The number of new cases of a disorder within

a given time period Prevalence:

The percentage of the population that has the disorder at a particular time

Duration: The average length of a given disorder

Incidence: The number of new cases of a disorder within

a given time period Prevalence:

The percentage of the population that has the disorder at a particular time

Duration: The average length of a given disorder

1616

Experimental DesignsExperimental Designs

Clinical Trials: Studying the effectiveness of treatments

Analogue Experiments: An experimental situation that is designed to

be analogous to “real life”

Clinical Trials: Studying the effectiveness of treatments

Analogue Experiments: An experimental situation that is designed to

be analogous to “real life”

1717

The Single-Case DesignThe Single-Case Design

1818

The Single-Case DesignThe Single-Case Design

1919

Recapping the Main PointsRecapping the Main Points

Characteristics of the Scientific Method Research Designs

Characteristics of the Scientific Method Research Designs

2020

End of Chapter 3End of Chapter 3

Research Methods in Abnormal PsychologyResearch Methods in Abnormal Psychology