demand characteristics and investigator effects Flashcards
(9 cards)
What are demand characteristics in psychological research?
Cues in the research situation that may lead participants to guess the aim and change their behaviour accordingly, which threatens the validity of the data.
How do demand characteristics affect validity?
They reduce internal validity because participants’ behaviour may not reflect their true thoughts or feelings, but rather what they think the researcher wants to see.
Examples of demand characteristics?
✔ Guessing the aim and behaving accordingly.
✔ Trying to please the researcher.
✔ Trying to sabotage the results (the “screw you” effect).
How can demand characteristics be controlled?
✔ Use deception or cover stories.
✔ Use a single-blind design (participants unaware of the condition they are in).
✔ Use independent groups or matched pairs designs.
What are investigator effects?
Any unintentional influence the experimenter has on participants’ behaviour or the outcome of the research, including tone of voice, body language, or expectations.
Examples of investigator effects?
✔ Leading questions or biased phrasing.
✔ Giving away expectations nonverbally.
✔ Interpreting ambiguous behaviour in line with hypotheses.
How do investigator effects impact validity?
They reduce internal validity by introducing experimenter bias, meaning findings may reflect the researcher’s expectations rather than genuine participant behaviour.
How can investigator effects be controlled?
✔ Use double-blind procedures (neither participant nor experimenter knows the condition).
✔ Use standardised instructions and automated procedures.
✔ Minimise personal contact.
What is a double-blind procedure?
A design where neither the participant nor the researcher interacting with them knows the condition they are in. This controls both demand characteristics and investigator effects.
