Research Methods
105 flashcards by MentisLibrary
Variables, designs, validity, sampling, ethics, and statistics, plus the replication crisis that reshaped the field. Every card names the pitfall that trips up real studies, not just the textbook definition.
- What is an independent variable?
- The variable the researcher manipulates or selects to test its effect.
- What is a dependent variable?
- The variable measured to see whether the independent variable had an effect.
- What is a confounding variable?
- A variable that varies systematically with the independent variable and offers an alternative explanation for the result.
- What is an extraneous variable?
- Any variable other than the independent variable that could influence the dependent variable, whether or not it is confounded with condition.
- What is an operational definition?
- A precise statement of how a construct is measured or manipulated in a particular study.
- What is a construct?
- An abstract concept, not directly observable, that a study aims to measure or manipulate.
- What is the difference between a mediator and a moderator?
- A mediator explains how or why an effect occurs and sits on the causal path; a moderator changes the strength or direction of the effect.
- What is a control variable?
- A variable held constant or statistically adjusted so it cannot vary with condition.
- What is random assignment?
- Allocating participants to conditions by chance so that groups are expected to be equivalent on all variables before the manipulation.
- What is random sampling?
- Selecting participants from a population so every member has a known, nonzero chance of inclusion.
- What is the difference between random sampling and random assignment?
- Random sampling supports generalizing to a population; random assignment supports causal inference within a study.
- What is a true experiment?
- A study with a manipulated independent variable, random assignment to conditions, and a comparison condition.
- What is a quasi-experiment?
- A study with a manipulated or naturally occurring independent variable but without random assignment.
- What is a correlational study?
- A study that measures variables without manipulation to assess their association.
- What is a between-subjects design?
- Each participant experiences only one condition, and conditions are compared across different people.
- What is a within-subjects design?
- Each participant experiences every condition, serving as their own control.
- What are order effects, and how are they controlled?
- Effects of the sequence in which conditions are presented, including practice and fatigue, controlled by counterbalancing or randomizing order.
- What is counterbalancing?
- Systematically varying the order of conditions across participants so order effects are distributed evenly.
- What is a factorial design?
- A design with two or more independent variables, each with multiple levels, crossed so that every combination is tested.
- What is an interaction effect?
- When the effect of one independent variable depends on the level of another.
- What is a main effect?
- The overall effect of one independent variable averaged across the levels of the others.
- What is a placebo control?
- A comparison condition that includes everything except the active ingredient, so expectancy effects are equated.
- What is a single-blind study?
- Participants do not know which condition they are in.
- What is a double-blind study?
- Neither participants nor the researchers interacting with them know condition assignment.
- What are demand characteristics?
- Cues that lead participants to guess the study's purpose and change their behavior accordingly.
- What are experimenter expectancy effects?
- Unintentional influence of the researcher's expectations on participants' behavior or on data recording.
- What is the Hawthorne effect?
- Behavior change caused simply by knowing one is being observed. Reanalyses of the original industrial data found the evidence far weaker than the popular version claims.
- What is internal validity?
- The extent to which a study supports the claim that the independent variable caused the change in the dependent variable.
- What is external validity?
- The extent to which findings generalize to other people, settings, times, and operationalizations.
- What is ecological validity?
- The extent to which the study's materials, task, and setting resemble those of the real world situation of interest.