Unit 0 Learning Celebration Study Guide

Ethical considerations / informed consent

rules intended to protect research participants.

Cause and effect

A relationship in which changes in one variable are produced by changes in another variable

Correlation coefficient (r)

A statistical measure ranging from −1.00 to +1.00 that indicates the strength and direction of a linear relationship between two variables. The closer the absolute value is to 1, the stronger the relationship

Maturation

Natural developmental changes that occur as an individual grows or ages.

Statistical significance

A statistical conclusion that an observed difference or relationship is unlikely to have occurred by chance alone, according to a predetermined significance level

Independent variable (IV)

The variable that the researcher manipulates in an experiment to determine whether it affects another variable.

Dependent variable (DV

The variable that the researcher measures to determine the effect of the independent variable.

Control group

The group in an experiment that does not receive the experimental treatment or receives the comparison condition. It provides a baseline against which the experimental group can be compared.

Mean

arithmetic average

Median

middle score when scores are ordered

Mode

most frequently occurring score

Humanistic perspective / free will

The humanistic perspective emphasizes people's capacity for personal choice, self-awareness, personal growth, and free will.

Meta-analysis

A statistical method that combines the results of multiple studies addressing the same question in order to estimate an overall effect or pattern

Positive skew / positive distribution

A distribution with a tail extending toward the higher/right scores

Negative skew / negative distribution

A distribution with a tail extending toward the lower/left scores.

Random sample

A sample selected from a population so that each member of the population has an equal or known chance of being selected. Random sampling helps make findings more generalizable to the population

True experiment

A research method in which the researcher manipulates an independent variable and measures a dependent variable, typically using random assignment to conditions

Problem-solving strategies

Methods used to reach a solution. An algorithm is a step-by-step procedure that guarantees a solution when correctly applied; a heuristic is a mental shortcut or rule of thumb that can be faster but may lead to error

Scatterplot / scattergram

A graph that displays pairs of scores for two variables. It allows researchers to see the direction and strength of a correlation and identify possible outliers

Cognitive psychology

The branch of psychology that studies mental processes, including thinking, memory, perception, attention, language, decision making, and problem solving

Sampling

The process of selecting participants from a population to take part in a research study

Frequency distribution

A representation of data showing how frequently each score or category occurs

Double-blind study/control

An experimental procedure in which both participants and the researchers who interact with or assess them do not know which condition participants are assigned to, helping reduce expectancy and researcher bias

Behaviorism

A psychological perspective that focuses on the study of observable behavior and how behavior is shaped by environmental conditions, learning, reinforcement, and punishment

Falsifiability

A characteristic of a scientific claim: it must be stated in a way that allows evidence to potentially show that the claim is false

Case study

A research method involving an in-depth investigation of one individual, group, or case, often using multiple sources of information. It provides detailed information but may have limited generalizability

Percentile rank

A score's position in a distribution indicating the percentage of scores that are at or below that score. Example: the 80th percentile means the score is at or above approximately 80% of the comparison group.

Normal distribution — 68%

A symmetrical, bell-shaped distribution. Approximately 68% of scores fall within one standard deviation of the mean; about 95% fall within two standard deviations and 99.7% within three

Convenience sampling

A sampling method in which researchers select participants who are readily available. It is convenient but may produce a biased or unrepresentative sample, limiting generalizability

Debriefing

The process of explaining the true purpose, procedures, and relevant information about a research study to participants after their participation, particularly when deception was used

Operational definition

A precise description of the operations or procedures used to measure a variable or manipulate it in a research study. It tells exactly how a concept is being measured.