Observation: The act of watching or noticing something carefully in order to obtain information. For example, psychologists often use observational methods to examine human behavior.
Analysis: The process of breaking down complex concepts into smaller parts in order to understand them better. In psychology research, analysis involves examining data and identifying patterns or relationships.
Investigation: Systematic inquiry or examination conducted with the purpose of uncovering facts or gathering evidence. Researchers often conduct investigations to examine specific psychological phenomena or theories.