ap psych unit 1 vocab

Hindsight Bias

The tendency to believe, after learning an outcome, that one would have foreseen it.

Overconfidence

The tendency to overestimate the accuracy of our beliefs, knowledge, and judgments.

Perceiving order in random events

The natural human tendency to see patterns, streaks, or meaning in purely random sequences of data.

Scientific method

A self-correcting process for evaluating ideas with observation and analysis using systematic steps.

Theory

An explanation using an integrated set of principles that organizes observations and predicts behaviors or events.

Hypothesis

A testable prediction, often implied by a theory.

Operational definition

A carefully worded statement of the exact procedures and measurements used in a research study.

Replication

Repeating the essence of a research study, usually with different participants in different situations, to see whether the basic finding extends to other circumstances.

Correlational methods

Research strategies that measure the degree of relationship between two or more naturally occurring variables without manipulating them.

Experimental methods

Research strategies in which an investigator manipulates one or more variables to observe the effect on a behavior or mental process, allowing for cause-and-effect conclusions.

Case study

A descriptive technique in which one individual or group is studied in depth in the hope of revealing universal principles.

Naturalistic observation

A descriptive technique of observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation.

Survey

A descriptive technique for obtaining the self-reported attitudes or behaviors of a particular group, usually by questioning a representative sample of that group.

Sampling bias

A flawed sampling process that produces an unrepresentative sample.

Population

All those in a group being studied, from which samples may be drawn.

Random sample/sampling

A sample that fairly represents a population because each member has an equal chance of inclusion.

Convenience sampling/samples

Selecting individuals who are easiest to reach or most readily available to participate in a study.

Falsifiability

The capacity for a hypothesis or theory to be proven wrong through testing or observation.

Peer review

The evaluation of scientific or academic work by other experts in the same field before publication to ensure quality and validity.

Quantitative measures

Research instruments that collect numerical data that can be analyzed statistically (e.g., Likert scales).

Qualitative measures

Research instruments that collect non-numerical, descriptive data to capture subjective experiences or open-ended responses (e.g., structured interviews).

Framing

The way an issue or question is presented, which can significantly affect decisions, judgments, and survey responses.

Social desirability bias

The tendency of survey respondents to answer questions in a manner that will be viewed favorably by others.

Self-report bias

The inaccuracy of data collected through self-reporting due to selective memory, exaggeration, or misunderstanding of questions.

Meta-analysis

A statistical technique for combining the results of multiple independent studies to determine overall trends or patterns.

Correlation

A measure of the extent to which two factors vary together, and thus how well either factor predicts the other.

Correlation coefficient

A statistical index of the relationship between two things, ranging from -1.00 to +1.00.

Variable

Any factor, trait, or condition that can exist in differing amounts or types and can be measured or manipulated.

Scatterplots

A graphed cluster of dots, each representing the values of two variables, used to display the strength and direction of a correlation.

Illusory correlation

Perceiving a relationship between two variables where none exists, or perceiving a stronger relationship than actually exists.

Regression toward the mean

The tendency for extreme or unusual scores or events to fall back toward their average on subsequent measurements.

Experiment

A research method in which an investigator manipulates one or more independent variables to observe their effect on a dependent variable while controlling other variables.

Experimental group

In an experiment, the group exposed to the treatment (the independent variable).

Control group

In an experiment, the group not exposed to the treatment, serving as a comparison for evaluating the effect of the treatment.

Randomly assign/random assignment

Assigning participants to experimental and control groups by chance, minimizing preexisting differences between the groups.

Double-blind procedure

An experimental procedure in which both the research participants and the research staff are ignorant about whether participants have received the treatment or a placebo.

Placebo effect

Experimental results caused by expectations alone; any effect on behavior caused by the administration of an inert substance or condition.

Independent variable

The factor in an experiment that is manipulated and whose effect is being studied.

Confounding variable

A factor other than the factor being studied that might produce an effect in an experiment.

Dependent variable

The outcome factor in an experiment; the variable that may change in response to manipulations of the independent variable.

Validity

The extent to which a test or experiment measures or predicts what it is supposed to.

Informed consent

An ethical principle requiring that research participants be told enough to enable them to choose whether they wish to participate.

Debriefing

The post-experimental explanation of a study, including its purpose and any deceptions, given to its participants.

Institutional Review Board

An administrative body established to protect the rights and welfare of human research subjects recruited to participate in research.

Ethical Guidelines

Sets of rules and principles designed to protect participants' safety, rights, and well-being in research studies.

Informed consent

(Duplicate term) An ethical requirement where adult participants are fully informed about a study and voluntarily agree to participate.

Informed assent

The agreement of a minor or individual unable to give legal consent to participate in a study, obtained alongside parental/guardian consent.

Protection from harm

The ethical obligation to ensure participants are not exposed to physical, mental, or emotional risk during research.

Confidentiality of participants

The ethical principle that personal data and identities of research participants must be kept private and secure.

Minimal deception

The rule that misleading participants should only occur when absolutely necessary for the study, and must never cause distress or harm.

Confederates

Individuals who pretend to be regular participants in an experiment but are actually working for the researcher.

Descriptive statistics

Numerical data used to measure and describe characteristics of groups, including measures of central tendency and variation.

Histogram

A bar graph depicting a frequency distribution of continuous variables.

Measures of central tendency

Single scores that represent the center or typical value of a data set (mean, median, mode).

Mode

The most frequently occurring score(s) in a distribution.

Mean

The arithmetic average of a distribution, obtained by adding the scores and then dividing by the number of scores.

Median

The middle score in a distribution; half the scores are above it and half are below it.

Skewed distribution

A representation of scores that lack symmetry around their average value, creating a tail toward one extreme.

Measures of variation

Statistics that describe how spread out or dispersed the data values are (e.g., range, standard deviation).

Range

The difference between the highest and lowest scores in a distribution.

Standard deviation

A computed measure of how much scores vary around the mean score.

Normal curve

A symmetrical, bell-shaped curve describing the distribution of many physical and psychological attributes, where about 68% of scores fall within one standard deviation of the mean.

Positive skew

A distribution where most scores cluster at the lower end, with a tail pointing toward higher values (mean is pulled higher than the median).

Negative skew

A distribution where most scores cluster at the higher end, with a tail pointing toward lower values (mean is pulled lower than the median).

Bimodal distributions

A frequency distribution that has two distinct peaks/modes.

Statistical significance

A statistical statement of how likely it is that an obtained result occurred by chance rather than due to the independent variable.