• Choose a category
• All
• Classic-Fiction

• Neuropsychologists explore the relationships between brain/nervous systems and behavior. Neuropsychologists are also called biological psychologists or biopsychologists, behavioral geneticists, physiological psychologists, and behavioral neuroscientists.

• Personality psychologists focus on traits, attitudes, and goals of the individual.

• Psychometricians (a.k.a. psychometric or measurement psychologists) focus on methods for acquiring and analyzing psychological data.

• Rehabilitation psychologists help clients with mental retardation, developmental disabilities, and disabilities resulting from stroke or accidents adapt to their situations.

• School psychologists assess and counsel students, consult with educators and parents, and perform behavioral intervention when necessary.

• Social psychologists focus on how a person’s mental life and behavior are shaped by interactions with other people.

• Sports psychologists help athletes refine their focus on competition goals, increase motivation, and deal with anxiety and fear of failure.

CHAPTER 6

Research Methods

IN THIS CHAPTER

Summary: In their scientific study of behavior and mental processes, psychologists aim to describe, understand, predict, and explain psychological phenomena. Theories are organized sets of concepts that explain phenomena. Psychologists conduct research to answer behavioral questions. They systematically collect accurate data through a variety of carefully made observations and measurements. Scientific experiments, naturalistic observations, interviews, questionnaires, case studies, and psychological tests are some methods psychologists use to explore our personalities, values, intelligence, talents, and the effects of heredity and environment on our development. The scientific method is a set of general procedures psychologists use for gathering and interpreting data. Other researchers working independently must be able to obtain similar results using the same methods; this is called replication.

This chapter examines research methods and statistics used to make sense of research data.

Key Ideas

Experimental Method

The Controlled Experiment

Eliminating Confounding Variables

Quasi-experimental Research

Correlational Research

Naturalistic Observation

Survey and Test Methods

Case Study

Elementary Statistics

Descriptive Statistics

Measures of Central Tendency

Measures of Variability

Correlation

Graphic Representation of Correlation

Inferential Statistics

Ethical Guidelines

Experimental Method

Some psychologists conduct experimental research in laboratories designed for carefully controlling conditions and measuring behavior.

The Controlled Experiment

The laboratory is one of the places where scientists test hypotheses, predictions of how two or more factors are likely to be related. Variables are factors that can have different values. In a scientific experiment, the researcher systematically manipulates a variable under controlled conditions, and observes the response. The factor the researcher manipulates is called the independent variable (IV). The dependent variable (DV) is the behavior or mental process that is being measured, the factor that may change as a result of manipulation of the independent variable. If the dependent variable changes when only the independent variable is changed, the researcher can conclude that the change in the independent variable caused the change in the dependent variable. Thus, the independent variable is the cause, and the dependent variable is the effect. A controlled experiment is the only research method that can establish a cause and effect relationship.

“There’s a good probability that one of the essays on the AP exam will focus on research methods, especially experiments.”

—Elliott S., AP Teacher

An effective way to determine the independent and dependent variables is to word the hypothesis in the form of an “If . . . , then . . .” statement. What follows the