Experimental Methods

Question 1

What is a lab experiment?

Answer 1

An experiment in a highly controlled environment where the researcher manipulates the IV and measures the DV. (AO1)

Question 2

Strength of lab experiments (cause & effect)?

Answer 2

High control → easier to establish cause and effect between IV & DV (↑ internal validity). (AO3)

Question 3

Strength of lab experiments (reliability)?

Answer 3

High reliability → can be repeated in same controlled conditions. (AO3)

Question 4

Limitation of lab experiments (ecological validity)?

Answer 4

Artificial environment → lacks ecological validity, hard to generalise to real life (↓ external validity). (AO3)

Question 5

Limitation of lab experiments (demand characteristics)?

Answer 5

Ppts may change behaviour due to clues → demand characteristics → ↓ internal validity. (AO3)

Question 6

What is a field experiment?

Answer 6

An experiment carried out in a natural setting (e.g. school, office) where the researcher manipulates the IV and measures the DV. (AO1)

Question 7

Strength of field experiments (validity)?

Answer 7

Less demand characteristics → ↑ internal validity. (AO3)

Question 8

Strength of field experiments (ecological validity)?

Answer 8

Real-life setting → ↑ ecological validity → easier to generalise findings. (AO3)

Question 9

Limitation of field experiments (reliability)?

Answer 9

Low reliability → hard to repeat in same natural conditions. (AO3)

Question 10

Limitation of field experiments (ethics)?

Answer 10

Risk of lack of informed consent if ppts don’t know they’re being studied. (AO3)

Question 11

What is a natural experiment?

Answer 11

An experiment where the IV is a naturally occurring event, not manipulated by the researcher. (AO1)

Question 12

Strength of natural experiments (opportunities)?

Answer 12

Allows study of variables that are unethical or impractical to manipulate (e.g. Rutter’s orphan study). (AO3)

Question 13

Strength of natural experiments (ecological validity)?

Answer 13

Often occur in real-life settings → ↑ ecological validity & generalisability. (AO3)

Question 14

Limitation of natural experiments (rarity)?

Answer 14

Events may occur rarely → limited opportunities → ↓ reliability. (AO3)

Question 15

Limitation of natural experiments (control)?

Answer 15

Low control over extraneous variables → hard to establish cause & effect → ↓ internal validity. (AO3)

Question 16

What is a quasi experiment?

Answer 16

An experiment with an IV based on existing differences (e.g. age, gender) which is not manipulated by the researcher. (AO1)

Question 17

Where can quasi experiments be carried out?

Answer 17

In natural or controlled environments (lab or field). (AO1)

Question 18

Limitation of quasi experiments (sample bias)?

Answer 18

Sample may have unique characteristics → hard to generalise → ↓ external validity. (AO3)