Types of Experiments

Question 1

What do experiments involve?

Answer 1

• A change of IV
• Recording of the subsequent effects on the DV
• Allowing observation of cause and effect

Question 2

Describe field experiments

Answer 2

• Controlled experiment conducted outside a laboratory. IV is manipulated and causal relationships can be demonstrated
• They have lower internal validity (less control over extraneous and confounding variables) and higher external validity (greater mundane realism)
• Participants are unaware they’re in a experiment so behaviour is more natural

Question 3

Describe laboratory experiments

Answer 3

• Conducted in a controlled settings
• Has high internal validity as there is control over all variables, but low ecological validity as participants are aware they’re being studied and tasks tend to be artificial

Question 4

Describe natural experiments

Answer 4

• Where researchers measure the effect of an IV on a DV.
• But the IV is a naturally occurring event, so IV can’t be directly manipulated as it would be unethical

Question 5

Describe quasi experiments

Answer 5

• Where researchers measure the effects of an IV on a DV
• But the IV is a naturally occurring characteristic of the participants, so it can’t be manipulated, it’s simply a difference between people that exists

Question 6

What are advantages of field experiments?

Answer 6

• Participants more likely to behave naturally (high internal validity) as they likely don’t know they’re being studied so they don’t respond to demand characteristics
• The tasks are less artificial (higher mundane realism and ecological validity) as it’s conducted in a natural settings

Question 7

What are disadvantages of field experiments?

Answer 7

• A more natural experiment could raise ethical issues if participants are unaware, as it’s questions their informed consent
• There’s less control over extraneous variables, so it has lower internal validity

Question 8

What is an advantage of laboratory experiments?

Answer 8

They’re well-controlled, so extraneous and confounding variables can be minimised, there’s high interval validity and there’s a strong cause and effect relationship established

Question 9

What are disadvantages of laboratory experiments?

Answer 9

• Participants may not behave naturally as they’re likely to know they’re being tested (demand characteristics) leading to lower internal validity
• There is an artificial setting and tasks, so results might be generalisable as it doesn’t represent everyday experiences. Leading to low mundane realism and ecological validity

Question 10

What are advantages of natural experiments?

Answer 10

• It studies real world events, so there’s high mundane realism and ecological validity
• Allows us to research events that would be unethical or impractical to manipulate

Question 11

What are disadvantages of natural experiments?

Answer 11

• There’s low control over confounding and extraneous variables, so there’s low internal validity
• It can’t demonstrate causal relationships because we can’t manipulate the IV directly

Question 12

What are the advantages of the quasi experiments?

Answer 12

• Allows us to compare between types of people
• Allows us to research characteristics that would be ethical or impractical manipulate

Question 13

What are the disadvantages of the quasi experiments?

Answer 13

• There’s low control over confounding and extraneous variables, as people may know they’re being studied, leading to low internal validity and demand characteristics
• It can’t demonstrate causal relationships as we can’t manipulate the IV