types of experiments

Question 1

What are the types of experiment?

Answer 1

• lab
• field
• natural
• quasi

Question 2

What is a lab experiment?

Answer 2

• An experiment conducted in a highly controlled environment where every variable can be carefully controlled.
• The researcher manipulates the IV and records the effect on the DV.

Question 3

What are strengths for a lab experiment?

Answer 3

• Well controlled
• extraneous/confounding variables minimised - higher internal validity
• Can be easily replicated

Question 4

What are limitations for a lab experiment?

Answer 4

• Artificial situation - results lack generalisability - low external validity
• Participants know they are in an experiment - demand characteristics
• Tasks participants are asked to carry out may not represent real life experience - low mundane realism

Question 5

What is a field experiment?

Answer 5

• The IV is manipulated in a natural, more everyday setting.
• The experiment is happening where we expect our behaviour to occur

Question 6

What are strengths for a field experiment?

Answer 6

• Less artificial compared to lab experiments - environment is more natural – usually higher mundane realism
• ppts behave as they would in everyday life
• higher ecological validity - reflects real life setting

Question 7

What are limitations for a field experiment?

Answer 7

• Loss of control of extraneous variables - harder to establish cause and effect
• Ethical issues – ppts unaware – cannot give consent, invasion of privacy

Question 8

What is a natural experiment?

Answer 8

The researcher takes advantage of a naturally occurring IV, therefore the researcher does not manipulate the IV.

Question 9

What are strengths for a natural experiment?

Answer 9

• Allows research where IV can’t be manipulated for ethical or practical reasons
• Enables psychologists to study real problems such as effects of a disaster on health - increased mundane realism and ecological validity

Question 10

What are limitations for a natural experiment?

Answer 10

• A naturally occurring event may only happen rarely - reducing opportunities for research and generalising findings to similar situations.
• Cannot demonstrate a causal relationship, because the IV is not directly manipulated
• Random allocation of participants to each condition not possible – confounding variabl

Question 11

What is a quasi experiment?

Answer 11

• have an IV that is based on an existing difference between people (e.g. age or gender). - no one has manipulated the variable, it simply exists.
• Physically can’t change the variable―it just exists
• Often treated like lab experiments, IV exists

Question 12

What are strengths for a quasi experiment?

Answer 12

• Allows comparisons between types of people
• Often carried out under controlled conditions so share the strengths of lab experiments

Question 13

What are limitations for a quasi experiment?

Answer 13

• Cannot randomly allocate participants to conditions – confounding variables
• Participants may be aware of being studied - demand characteristics