Unit 0: Research Methods and Background

Psychology

The scientific study of the mind and behavior.

Mental Processes

Internal operations of the mind that are not observable (e.g., cognition, emotion, perception, motivation).

Cognition

Acquiring knowledge through thought and experience.

Emotion (mental process)

Responses that help people react to events.

Perception

Organization of sensory information.

Motivation

Forces that explain why people act.

Human Behaviors

Observable actions or reactions of individuals, including physical actions, emotional responses, social interactions, and learned behaviors.

Humanism

Perspective focusing on personal growth, free will, and reaching one's full potential. Example: Maslow's hierarchy of needs.

Psychodynamic

Perspective emphasizing unconscious thoughts, childhood experiences, and inner conflicts. Example: Freud's theory of the unconscious mind.

Evolutionary Perspective

Explains behavior as adaptations that helped humans survive and reproduce. Example: fear of dangerous animals helped early humans survive.

Sociocultural Perspective

Examines how culture, social groups, and environment influence behavior and thinking.

Biological Perspective

Studies how the brain, nervous system, hormones, and genetics affect behavior and mental processes.

Behavioral Perspective

Focuses on observable behaviors learned through experience, rewards, and punishments.

Cognitive Perspective

Studies mental processes such as thinking, memory, perception, language, and problem solving.

Theory

An organized explanation that helps describe and predict behavior or events based on evidence and research.

Falsifiable Hypothesis

A statement that can be tested and potentially proven wrong using evidence or data; a core requirement of scientific thinking.

Operational Definition

A clear explanation of how a concept will be measured or tested in a study.

Replication

The process of repeating a study to see if the same results can be obtained.

Peer Review

When experts in the same field evaluate the quality, accuracy, and validity of research before it is published.

Non-experimental Research

A researcher observes or studies behavior without manipulating variables or assigning treatments; cannot determine cause and effect.

Case Study

An in-depth investigation of one person, group, or event.

Correlational Study

Looks at the relationship between two variables to see if they are related, but does not show cause and effect.

Meta-analysis

A study that combines and analyzes results from many different studies on the same topic.

Naturalistic Observation

Observing behavior in a natural environment without interference.

Longitudinal Study

A group of subjects are studied over a long period of time.

Cross-sectional Study

A representative cross section of the population is tested or surveyed at one specific time.

Cohort-sequential Study

A cross section of the population is chosen and then each cohort is followed for a short period of time.

Measures of Central Tendency

Statistics that describe the center of a data set (mean, median, mode).

Variation

How spread out or different the data values are from each other.

Percentile Rank

The percentage of scores that fall below a specific score.

Normal Curve

A symmetrical, bell-shaped distribution where most scores cluster around the mean.

Bimodal Distribution

A data set with two most common values (two peaks).

Standard Deviation

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

Wording Effect

When the way a question is phrased influences how people respond.

Self-Reporting Bias

When people give inaccurate answers about themselves, often to look better or due to memory errors.

Sample

A smaller group taken from a larger population that researchers study.

Representative Sampling

A sample that accurately reflects the characteristics of the larger population.

Convenience Sampling

Choosing participants because they are easy to reach or available; may not represent the broader population.

Experimenter Bias

When a researcher's expectations or opinions unintentionally influence the results of a study.

Social Desirability Bias

When people answer questions in ways they think will make them look good or acceptable to others.

Correlational Data

Information that shows whether two variables are related or connected.

Positive Correlation

A relationship where both variables increase together or decrease together.

Negative Correlation

A relationship where one variable increases while the other decreases.

Correlation Coefficient

A number from -1 to +1 that shows the strength and direction of a correlation (+1 = perfect positive, -1 = perfect negative, 0 = no correlation).

Illusory Correlation

Believing there is a relationship between two variables when there really is little or none.

Regression to the Mean

The tendency for unusually high or low results to move closer to the average over time.

Experimental Methodology

The researcher manipulates one or more variables to observe the effect on another variable, allowing cause-and-effect relationships to be established.

Experimental Group

The group that receives the treatment or independent variable being tested.

Control Group

The group that does not receive the treatment and is used for comparison.

Placebo Effect

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

Single Blind Study

A study where participants do not know whether they are in the experimental or control group.

Double Blind Study

A study where neither the participants nor the researchers interacting with them know who received the real treatment.

Likert Scale

A rating scale used to measure opinions, attitudes, or feelings (e.g., 1 = Strongly Disagree to 5 = Strongly Agree).

Psychological Tests

Standardized tests designed to measure mental abilities, personality traits, or behaviors (e.g., IQ test, Big Five).

Physiological Measures

Methods used to record physical responses of the body during specific situations (e.g., heart rate, brain activity, sweating).

Surveys

A common method of collecting information by asking people specific questions.

Institutional Review Board (IRB)

A committee that reviews research studies to make sure they are ethical and protect participants' rights, safety, and informed consent.

Informed Consent

Participants are told important information about a study (purpose, risks, right to quit) before agreeing to participate.

Protection from Harm

Researchers must avoid causing physical or psychological harm to participants.

Confidentiality

Keeping participants' personal information and responses private (e.g., using ID numbers instead of names).

Deception

Misleading participants about part of a study when necessary for valid results.

Debriefing

Explaining the true purpose of a study to participants after it ends.

Institutional Animal Care and Use Committee (IACUC)

A committee that oversees research involving animals to ensure humane treatment.

Hindsight Bias

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

Overconfidence

Subjective confidence is reliably greater than the objective accuracy of judgements.

Perceiving Order

The natural tendency to see meaningful patterns even in random events.

Sampling Bias

A flawed process producing an unrepresentative sample that confirms a hypothesis.

Scatter Plot

A graph that shows the relationship between two variables using dots.

Effect Size

A measure of how strong or important a result or relationship is.

Statistical Significance

A result that is unlikely to have happened by chance alone.

Third Variable Problem

When an outside variable may explain the relationship between two studied variables (e.g., weather affecting both ice cream sales and drowning rates).