Research methods Flashcards
What are the four types of experiments?
Lab, Field, Natural, Quasi.
What is a lab experiment?
Conducted in a highly controlled environment to establish causality. Strengths: High internal validity, replicable. Weaknesses: Low ecological validity, risk of demand characteristics.
Field Experiments
Conducted in a natural environment where the IV is still manipulated. Strengths: Higher ecological validity, more natural behaviour. Weaknesses: Less control over extraneous variables, ethical concerns (informed consent).
Natural Experiments
The IV changes due to external factors rather than researcher manipulation. Strengths: High external validity, allows for study of real-world effects. Weaknesses: No control over IV, difficult to replicate.
Quasi-Experiments
Participants are not randomly assigned to conditions (e.g., gender differences in cognition). Strengths: Allows research on variables that cannot be ethically manipulated. Weaknesses: Cannot establish cause and effect due to lack of randomization.
Key Terms in Experimental Methods:
Independent Variable (IV): The variable manipulated by the researcher.
Dependent Variable (DV): The variable measured to assess the effect of the IV.
Operationalisation: Defining variables in a way that makes them measurable.
Extraneous Variables: Any variable other than the IV that may affect the DV.
Confounding Variables: Variables that systematically vary with the IV, affecting results.
Demand Characteristics: Cues in an experiment that may influence participants’ behavior.
Investigator Effects: When the researcher unintentionally influences the outcome.
Standardisation: Keeping procedures consistent to ensure reliability.
Random Allocation: Assigning participants to conditions randomly to reduce bias.
Experimental Design
Independent Groups Design: Different participants in each condition. Strengths: No order effects. Weaknesses: Participant variables may affect results.
Repeated Measures Design: Same participants take part in all conditions. Strengths: Controls participant variables. Weaknesses: Order effects (e.g., practice, fatigue).
Matched Pairs Design: Participants are paired based on characteristics relevant to the study. Strengths: Controls participant variables. Weaknesses: Time-consuming to match pairs.
Ethical Considerations in Experiments
Informed Consent: Participants must be fully informed about the study’s purpose.
Deception: Should be minimized and justified, followed by debriefing.
Right to Withdraw: Participants should be able to leave the study at any time.
Confidentiality: Participants’ data must remain anonymous.
Protection from Harm: Researchers must ensure participants are not subjected to distress.
