Experimental methods

Question 1

What are the 4 experimental methods?

Answer 1

• Laboratory
• Field
• Natural
• Quasi

Question 2

What is the purpose of laboratory experiments?

Answer 2

To establish a cause and effect relationship between the IV and the DV

Question 3

Where do laboratory experiments take place?

Answer 3

In a controlled environment so there are fewer extraneous variables such as noise and temperature

Question 4

Describe the strengths of laboratory experiments

Answer 4

• Control of IV
• Accurate measurement of the DV (correct analysis of data)
• Control over extraneous variables which limits unwanted background variables which could effect the outcome of the experiment
• Limits confounding variables which limits any participant change
• Replication of results is possible using the same methods

Question 5

Describe the limitations of laboratory experiments

Answer 5

• Lacks generalisability so can’t be applied to other situations
• Low ecological validity because its not a real world setting
• Demand characteristics mean that it doesn’t provide meaningful conclusions as people may act differently
• Low mundane realism as a lab isn’t a real world setting so people may act different

Question 6

Describe field experiments

Answer 6

• Take place in a natural environment
• Basic scientific procedures are followed

Question 7

Describe an example of a field experiment

Answer 7

The Subway Samaritan
- Passenger falls on the New York subway (38 drunk and 65 with a cane)
- Passengers were participants but they didn’t know and students amongst the public acted as observers
- The aim was to see what factors lead people to help someone

Question 8

describe the strength of field experiments

Answer 8

higher ecological validity

Question 9

describe the limitations of field experiments

Answer 9

• loss of control
• extraneous variables
• ethics - people don’t know they’re involved so they can’t consent

Question 10

describe natural experiments

Answer 10

• researcher makes use of naturally occurring variables but they therefore can’t manipulate the IV
• they’re used to investigate topics that would be impossible r unethical to do in a lab/ the field
• e.g. the war in Finland

Question 11

describe the strengths of natural experiments

Answer 11

• provides an opportunity for research that wouldn’t otherwise be possible
• high ecological validity

Question 12

describe the limitations of natural experiments

Answer 12

• lacks generalisability
• lacks opportunity for study
• can’t randomly allocate participants to a condition

Question 13

describe quasi experiments

Answer 13

• features of a lab experiment but the IV is a characteristic of the participant so therefore isn’t quite a ‘real’ experiment
• e.g. gender/age

Question 14

describe the strengths of quasi experiments

Answer 14

• control of Iv
• accurate measurement of DV
• control over extraneous variables
• limits confounding variables
• replication of results is possible using the same methods

Question 15

describe the limitation of quasi experiments

Answer 15

• can’t randomly allocate participants to a condition