AP Psych Unit 0

Critical Thinking

Thinking deeply, evaluating evidence and questioning assumptions rather than accepting statements blindly.

Hindsight Bias

The tendency to believe, after learning the outcome, that one would have predicted it (I knew it all along).

Peer Reviewers

Experts who evaluate research before it is published to ensure quality and accuracy.

Theory

A well tested explanation of observed phenomena.

Hypothesis

A testable prediction derived from a theory.

Operational Definition

A precise description of how a variable is measured or manipulated.

Replication

Repeating a study to see if results are consistent.

Case Study

In depth analysis of one individual or small group.

Naturalistic Observation

Observing behavior in its natural environment without interference.

Survey

A method of gathering self reported attitudes or behaviors from a group.

Social Desirability Bias

The tendency to respond in a way viewed favorably by others.

Self Report Bias

Errors in participants responses due to memory, exaggeration, or dishonesty.

Sampling Bias

When a sample does not represent the population accurately.

Random Sample

A sample in which every member of the population has an equal chance of selection.

Population

The entire group a researcher is interested in studying.

Correlation

A measure of the relationship between two variables.

Correlation Coefficient

A statistical value ranging from minus one to plus one that describes the strength and direction of a correlation.

Variable

Anything that can change or vary in a study.

Scatterplot

A graph that shows the relationship between two variables.

Illusory Correlation

Perceiving a relationship between variables that does not actually exist.

Regression Toward the Mean

The tendency for extreme scores to move closer to the average on subsequent tests.

Experiment

Research method where one variable is manipulated to see its effect on another.

Experimental Group

The group exposed to the independent variable.

Control Group

The group not exposed to the independent variable used for comparison.

Random Assignment

Assigning participants to groups by chance to reduce bias.

Single Blind Procedure

Participants do not know which group they are in.

Double Blind Procedure

Neither participants nor experimenters know who is in which group.

Placebo Effect

Improvement resulting from belief in treatment rather than the treatment itself.

Independent Variable

The variable that is manipulated.

Confounding Variable

An unintended variable that might affect the dependent variable.

Experimenter Bias

When a researchers expectations influence the outcome of a study.

Dependent Variable

The outcome that is measured.

Validity

The extent to which a study measures what it claims to measure.

Quantitative Research

Research that collects numerical data.

Qualitative Research

Research that collects descriptive non numerical data.

Informed Consent

Participants must know the purpose and risks before participating.

Debriefing

Explaining the study and its purpose to participants after it ends.

Descriptive Statistics

Methods for summarizing data such as mean median and mode.

Histogram

A bar graph showing the frequency distribution of data.

Mode

The most frequently occurring score.

Mean

The arithmetic average of scores.

Median

The middle score when all scores are arranged in order.

Percentile Rank

The percentage of scores that fall below a given score.

Skewed Distribution

When data is not symmetrical it can be positively or negatively skewed.

Range

The difference between the highest and lowest scores.

Standard Deviation

A measure of how spread out scores are around the mean.

Normal Curve

A symmetrical bell shaped distribution.

Inferential Statistics

Methods used to determine if results can be generalized to a larger population.

Meta Analysis

A statistical analysis combining results from multiple studies.

Statistical Significance

The likelihood that results are not due to chance.

Effect Size

A measure of the strength of a relationship or the magnitude of an experimental effect.