Research Methods in Psychology: Key Terms and Definitions

A comprehensive vocabulary review of psychological research methods, covering forms of knowing, research design concepts, experimental threats, measurement scales, and methodology.

Logic

Knowledge derived from rules of thinking

Intuition

Unquestioning acceptance of one’s own

Authority

Knowledge based on information from a “credible ”

Folk wisdom/common sense

Appealing to what one expects else to know

Experience

Relying on experience to make decisions

Determinism

The assumption that the universe is

Empiricism

The idea that we understand the world through structured, systematic

Parsimony

The preference for the explanation when multiple explanations fit the same observations

Testability

The requirement that a scientific idea can be subjected to empirical

Falsifiability

The ability of a theory or hypothesis to be proven through observation or experiment

Theory

An overarching framework used to organize and explain phenomena and

Hypothesis

A tentative statement about the relationship between different

Prediction

A specific statement about the expected of a study

Deduction

A form of reasoning that moves from the general to the

Induction

A form of reasoning that moves from the specific to the

Abduction

Reasoning used in the absence of an established

Oversimplification

The process of reducing a complex concept into a form

Conceptual variable

An abstract construct that researchers want to measure but cannot directly

Essentialism

The assumption that an entity has an unchanging underlying

Operationism

An approach that defines variables using tangible procedures that can be used to them

Operational definition

A specific procedure used to measure or manipulate a variable for the purposes of a particular

Binary variable

A variable with only two possible response

Correlation

A nonexperimental design in which researchers variables without manipulating them

Correlation coefficient

A statistic that indicates the degree of relationship between two variables

Causation

A relationship in which a change in one variable produces a change in another

Bi-directionality problem

The problem of determining which variable influences the

Third-variable problem

The problem in which an external variable causes changes in both measured

Internal validity

The extent to which researchers can infer that one variable causes changes in another

Covariation

A relationship in which two variables change

Temporal precedence

The requirement that a cause occur its effect

Independent variable

The variable that is by the researcher

Dependent variable

The variable expected to be changed by the variable

Confound

A variable that changes alongside the independent variable and could explain all or part of the

Random assignment

A procedure that places participants into conditions without a systematic

Creativity

The ability to ideas

Priming

A procedure that presents something to influence a person’s

Demand characteristics

Features of an experiment that may reveal its to participants

Participant reactance

A participant’s attempt to help or the hypothesis

Evaluation apprehension

Anxiety or stress that occurs when participants know they are being

Single-blind study

A study in which participants are kept unaware of the study’s

Distractor/filler items

Questions or items that have little to do with the actual

Experimenter expectancy effect

A researcher’s unconscious manipulation of an experiment to produce an effect

Double-blind study

A study in which both the experimenter and participants are unaware of the study’s

Interaction effects

Effects in which social aspects of the researcher-participant interaction influence the

Biosocial effect

An effect in which biological factors and social environments interact to shape behavior and personality

Psychological effect

An effect in which the researcher’s attitudes or personality traits affect the

Ceiling effect

A problem occurring when a task is too easy and scores cluster near the of the scale

Floor effect

A problem occurring when a task is too difficult and scores cluster near the of the scale

Strong IV

An independent-variable manipulation designed to create a change in the dependent variable

Weak IV

An independent-variable manipulation designed to make small adjustments or fine in the dependent variable

Tough DV

A dependent-variable measure that is to change

Sensitive DV

A dependent-variable measure that changes

Straightforward manipulation

A manipulation that directly presents participants with a stimulus expected to influence the

Staged manipulation

A manipulation that indirectly elicits a psychological by making participants feel as though they are in a particular situation

Confederate

A person working with the researcher who acts as a regular in a study

Manipulation check

A method used to quantify whether a manipulation was

Self-report measure

A measure that asks participants about their explicit attitudes, judgments, thoughts, or

Behavioral measure

A measure based on observing, assessing, measuring, or coding someone’s

Physiological measure

A measure involving biological data from outside the

Rating scale

A measure using closed-ended responses to assess the degree of a

Anchor/label

A word or value that gives meaning to a number on a rating

Likert scale

A rating scale with specific, exact

Likert-type scale

A rating scale in which the original anchors or labels have been

Semantic differential scale

A scale with two at opposite ends of a number line

Nonverbal scale

A scale used to measure something difficult to or conceptualize

Forced choice

A question format that limits respondents to a selected set of

Double-barreled question

A question that asks about multiple in a single item

Loaded/leading question

A question whose intended is obvious

Negative wording

Question wording that uses or negations

Yea-saying

The tendency to with all questionnaire items

Nay-saying

The tendency to with all questionnaire items

Fence sitting

The tendency to select a response for all items

Reverse-scored question

A question reworded so that its meaning is to the construct being measured

Between-subjects design

A design in which each participant is exposed to only one

Posttest-only design

A design in which participants are tested only the manipulation

Pretest-posttest design

A design in which participants are tested before and an intervention

Concurrent-measures design

A design in which participants are exposed to multiple conditions at approximately the same

Repeated-measures design

A design in which participants are exposed to experimental conditions

Order/carryover effect

An effect in which a response in one condition is affected by participation in another

Fatigue effect

A decline in performance caused by becoming tired or

Practice effect

Improved performance caused by experience with a previous

Contrast effect

An effect in which participants judge one condition by comparing it with a previous

Counterbalancing

A procedure that switches the of experimental conditions

Latin square

A method for creating a cost-effective arrangement of different condition

True score theory

The idea that an observed score consists of a true score plus

Systematic error

A predictable pattern within otherwise variation

Single-case design

A research design involving a very small number of

ABA reversal design

A design that follows the sequence baseline, experimental condition, and

ABAB reversal design

A design that includes reversals between baseline and experimental conditions

Multiple-baseline design

A design that introduces an intervention across multiple baselines at different

Quasi-experimental design

A design without random assignment that uses groups

One-group posttest-only design

A design in which an outcome is measured once after an intervention in a nonrandom

One-group pretest-posttest design

A design in which an outcome is measured before and an intervention in a nonrandom group

Nonequivalent control group

A comparison group formed without random

History threat

An external event that affects participants between two

Maturation threat

Changes in participants that occur naturally over