Types Of Experiment

Question 1

Lab experiments + evaluate

Answer 1

Conducted in highly controlled environment

Strengths:
- control over confounding variables (CV) and extraneous variables (EV) - know that the IV caused the DV = internal validity
- replication is possible - check the results of the study

Limitations:
- lack generalisability; artificial
- demand characteristics; unnatural beh

Question 2

Field experiments + evaluate

Answer 2

The IV is manipulated in a natural everyday setting - researcher goes to the home of pts

Strength:
- higher mundane realism - the beh shown is more valid - pts unaware they are being studied (external V)

Limitation:
- no control of the confounding v and EV
… the cause and effect of the DV and IV is harder to establish
- ethical issues of privacy

Question 3

Natural experiment + evaluate

Answer 3

The change of the IV is not brought about by the researcher and would have happened if the R wasn’t there e.g. natural disaster

Strengths:
- high external validity; they study real world issues as they happen

Limitation:
- naturally occurring events happen rarely; reduces chance for research, can’t generalise to other situations
- pts may not be randomly allocated to experimental conditions - R less sure if the IV caused the DV

Question 4

Quasi experiments + evaluate

Answer 4

The IV has not been determined by anyone - it just exists, not been manipulated

Strengths:
- carried out under controlled conditions

Limitations:
- cannot randomly allocate pts to the conditions; may be confounding variables
- IV not controlled by the researcher so we are unsure whether the IV caused the DV