Introduction to Psychology: Psychological Research

Vocabulary terms and definitions regarding the scientific method and research methodologies in psychology based on lecture notes.

Empirical

Results that are grounded in objective, tangible evidence that can be observed time and time again, regardless of who is observing.

Hypothesis

A tentative and testable statement about the relationship between two or more variables.

Theory

A well-developed set of ideas that propose an explanation for observed phenomena.

Fairness

A component of the scientific method implying that all data must be considered when evaluating a hypothesis.

Falsifiable

The requirement that it should be possible to disprove a theory or hypothesis by experimental results.

Predictability

The implication that a theory should enable the making of predictions about future events.

Verifiability

The requirement that an experiment must be replicable by another researcher.

Institutional Review Board (IRB)

A committee of administrators, scientists, and community members that reviews proposals for research involving human participants to ensure they are not harmed.

Descriptive research

Research studies used to describe general or specific behaviors and attributes that do not test items for specific relationships between variables.

Correlational research

Research that tests whether a relationship exists between two or more variables.

Experimental research

Research that tests a hypothesis to determine cause and effect relationships.

Clinical or case study

An observational research study focusing on one or a few people.

Naturalistic observation

The observation of behavior in its natural setting.

Survey

A list of questions answered by research participants using a sample to learn more about a population.

Archival research

A method using past records or data sets to answer research questions or search for patterns and relationships.

Cross-sectional research

Research that compares multiple segments of a population at a single time.

Longitudinal research

Studies in which the same group of individuals is surveyed or measured repeatedly over an extended period of time.

Cohort-sequential research

Research that combines aspects of cross-sectional and longitudinal research.

Generalize

To infer that the results for a sample apply to the larger population.

Observer bias

When observations are skewed to align with the expectations of the observer.

Inter-rater reliability

A measure of agreement among observers on how they record and classify a particular event.

Correlation coefficient

A number from $-1$ to $+1$ that indicates the strength and direction of the relationship between variables.

Confounding variable

An outside factor that could be causing systematic movement in variables, or when two variables are linked making it difficult to sort out specific effects.

Random sample

A representative group that ensures the participants represent the larger population researchers are studying.

Random assignment

The process of assigning participants to control or experimental groups to prevent differences other than the independent variable.

Operational Definition

A clear description of how variables will be measured so the experiment can be understood and replicated.

Independent Variable

A condition or event that an experimenter varies in order to see its impact on another variable.

Dependent Variable

The variable thought to be affected by manipulation of the independent variable; usually a measurement of participant behavior.

Extraneous Variables

Any variables other than the independent variable that seem likely to influence the dependent variable in a specific study.

Double blind study

A study where both researchers and participants do not know which group received the treatment to prevent bias.

Placebo effect

The influence of people’s expectations or beliefs on their experience in a given situation.