AP Psych Unit 0

Critical thinking

Thinking that examines assumptions

Hindsight bias

Tendency to believe after learning an outcome that one would have predicted it

Peer reviewers

Experts who evaluate research for accuracy and quality before publication

Theory

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

Hypothesis

A testable prediction often implied by a theory

Operational definition

Definition of a concept in terms of the procedures used to measure or manipulate it

Replication

Repeating a study to see if results can be consistently reproduced

Case study

In-depth study of one individual or group

Naturalistic observation

Observing and recording behavior in its natural environment without interference

Survey

A technique for ascertaining self-reported attitudes or behaviors of a group

Social desirability bias

Tendency of participants to respond in a way that will be viewed favorably

Self-report bias

Distortion in responses due to desire to present oneself positively or inaccurately

Sampling bias

When a sample is not representative of the population

Random sample

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

Population

The entire group being studied

Correlation

A measure of the relationship between two variables

Correlation coefficient

A statistical index (r) of the relationship between two variables

Variable

Anything that can vary and is measurable

Scatterplot

A graph of plotted points showing the relationship between two variables

Illusory correlation

Perceiving a relationship where none exists

Regression toward the mean

The tendency for extreme scores to return toward the average

Experiment

A research method in which one variable is manipulated to observe its effect on another

Experimental group

Group exposed to the treatment or independent variable

Control group

Group not exposed to the treatment; serves as comparison

Random assignment

Assigning participants to groups by chance to control for preexisting differences

Single-blind procedure

Participants do not know if they are in the experimental or control group

Double-blind procedure

Neither participants nor experimenters know which group participants are in

Placebo effect

Experimental results caused by expectations alone

Independent variable

The factor that is manipulated

Confounding variable

An outside factor that may affect the outcome of an experiment

Experimenter bias

When researchers' expectations influence the outcome

Dependent variable

The outcome measured; affected by the independent variable

Validity

Extent to which a test measures what it claims to measure

Quantitative research

Research that collects numerical data for statistical analysis

Qualitative research

Research that explores experiences and meanings through non-numerical data

Informed consent

Participants' agreement to take part in research after understanding risks and benefits

Debriefing

Explaining the purpose and results of a study to participants afterward

Descriptive statistics

Statistics that summarize data (mean

Histogram

A bar graph representing frequency distribution of data

Mode

The most frequently occurring score

Mean

Average of all scores

Median

Middle score in a distribution

Percentile rank

Percentage of scores below a specific score

Skewed distribution

When data is asymmetrical

Range

Difference between the highest and lowest scores

Standard deviation

A measure of how spread out scores are around the mean

Normal curve

Bell-shaped distribution with most scores near the mean

Inferential statistics

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

Meta-analysis

Combining results of multiple studies to draw a conclusion

Statistical significance

Indicates likelihood that a result is not due to chance

Effect size

Measure of the magnitude of a treatment effect or relationship