Research methods:Experiment Types And Designs

Question 1

Lab experiment

Answer 1

Highly controlled, manipulate IV.
Prevents confounding variables + shows cause and effect
Low ecological validity, so not generalisable + ethical issues
- use random selection + standardisation, counterbalancing

Question 2

Field experiment

Answer 2

Done in everyday environment, manipulate IV, participants unaware that experiment is taking place.
High ecological validity, less likelihood of demand characteristics
Confounding variables, lack of informed consent, Hawthorne effect
- right to withdraw

Question 3

Natural experiment

Answer 3

Cannot manipulate IV, event being investigated has already happened. everyday environment or participant.
High ecological validity, less likelihood of demand characteristics, often used when manipulating IV is unethical.
Expensive and time consuming, sample bias, lack of informed consent.
- obtain consent

Question 4

Quasi experiment

Answer 4

Cannot manipulate IV. IV is characteristic of person.
More feasible, allows comparisons between people and can see general trends.
Random assignment can’t be used, leading to confounding variables, less internal validity, less generalisability.
- Use matched pairs design to reduce confounding variables

Question 5

Repeated measures design

Answer 5

Same participants in each condition of the IV.
Participant variables reduced. Less people needed.
X: Order effect.
- counterbalancing should be used

Question 6

Independent groups design

Answer 6

Different participants in each condition of the IV.
Avoids effects like fatigue, No order effect, they’re less likely to guess aim.
Lack of control over participant variables, needs more participants.
- Random assignment should be used.

Question 7

Matched pairs design

Answer 7

Pairs of participants are matched in terms of key variables like age or IQ.
Less participant variables so differences minimised. No order effect.
But not possible to control all participant variables and Time consuming.
- conduct a pilot study to consider key variables that might be important.

Question 8

aims of pilot studies

Answer 8

the methodology
allows for improvements and modifications
check if valid or reliable
check ambiguities or confusion in info/qs