Research methods

Question 1

Lab experiment

Answer 1

• Conducted in an artificial environment where all other extraneous variables that could affect the dependent variable are controlled.
• Designed with one clear independent variable and dependent variable which are operationalised (measurable).
• Participants can be randomly allocated into the conditions.
• Increases internal validity.
• Decreases ecological validity -> due to the artificiality of the situation.
• Control over variables allows for causality to be established.
• Reliability is high due to the use of standardised procedures -> allows for replication.
• Participants may exhibit demand characteristics -> questions the validity of results.

Question 2

Quasi experiment

Answer 2

• Different from lab experiments as the allocation of participants is not conducted randomly
• Participants are grouped based on their characteristics of interest (e.g. gender, ethnicity)
• Researchers are measuring pre-existing differences in one variable. Allows researchers to conduct experiments on pre-existing groups (e.g. gender differences in anxiety)
• Researchers cannot manipulate the IV as it already exists (e.g. gender)
  E.G. 2 groups attempt to memorise a list of words. One group of people have depression. One group of people don’t. The participants cannot be randomly allocated as the variable that we want to study is depression.
• IV is not manipulated by researchers -> causality cannot be established because we cannot be sure of the equivalence of comparison groups at the start of a study (becomes correlational)
• Pre-existing groups may be presented with unexpected confounding variables (a variable that has not been controlled)

Question 3

Field experiment

Answer 3

• Take place in a real-life setting (for the participants) like a natural setting
• Participants are NOT randomly allocated into conditions
• The Independent variable is manipulated
• Not all extraneous variables can be controlled (e.g. weather) so it is difficult to establish causality
• Ecological validity is increased
• Decreases internal validity
• Participants are unlikely to suffer from demand characteristics

Question 4

Natural experiment

Answer 4

• Conducted in participants’ natural environment
• Researchers do not manipulate any variables
• Participants are not randomly allocated to groups
• The independent variable is naturally occurring
• Researchers just measure the impact of DV