TYPE OF EXP AO1 & AO3

Question 1

types of experimental methods

Answer 1

• Conditions under which an experiment is carried at:

Dependent on:
oHow much control we have over IV
o How much control we have over extraneous variables

o Decision betweenreliability OR validity
o Lab, field, quasi + natural

Question 2

Lab experiments

Answer 2

• In environment that allows high degree of control over extraneous variables
• e.g. skinners box
• Controls variation of IV and measures change of DV

Question 3

lab experiment ADVANTAGE

Answer 3

• More confident of relationship between IV + DV being casual
• High degree of control = method more easily reliable = method is reliable

Question 4

lab experiment DISADVANTAGE

Answer 4

• High degree of control = situation is artificial = lack ecological validity (do not reflect natural behaviour)
• Lack mundane (everyday) realism

Question 5

field experiments

Answer 5

• In real world setting
• Researcher still manipulates IV but little control over extraneous variables
• Pts don’t know they are taking part in experiment

Question 6

Field experiments ADVANTAGE natural environment + demand characteristics

Answer 6

• More natural environment pp more comfortable therefore and behaviour is authentic results may be generalisable to everyday life
• Pp are unaware they’re being studied so less likely to show demand characteristics they’ll behave normally the study has greater external validity

Question 7

Field experiment DISADVANTAGE more difficult control over CV/DV + Ethical issues

Answer 7

• more difficult control CV/EV, observed changes in the DV may be due to the IV, instead.
• It is difficult to establish cause and effect than in the lab
• There are ethical issues pp in a field experiment may not have given informed consent

Question 8

Natural experiment

Answer 8

• the exp doesn’t manipulate the IV - it changed however not made by the exp
• someone or something else causes the IV to vary. (DV may be naturally occurring)
• E.G exam results

Question 9

Natural exp ADVANTAGE maybe only practical / ethical option + greater external validity

Answer 9

• It may be unethical to manipulate IV e.g studying the institutionalsation of children
• Natural experiments involve real world such as the effects of a natural disaster on stress levels

Question 10

Natural exp DISADVANTAGE the Natural event may occur rarely + pp are not randomly allocated

Answer 10

• many natural events are ‘one off’ and this reduces the opportunity for research
• The experimenter has no control over which pp are placed in which conditions
  May results in CV e.g romanian orphans adopted early May be friendly ones

Question 11

Quasi experiment

Answer 11

• when IV is an individual difference e.g. gender, intelligence may be naturally occuring

Question 12

Quasi exp ADVANTAGE there is often high control + comparisons can be made

Answer 12

• Often carried out in controlled conditions and therefore shares some of the strengths of lab experiments this means it can be replicated
• In a quasi experiment the IV is a difference between people this means comparisons can be made

Question 13

Quasi exp DISADVANTAGE pp arent randomly allocated

Answer 13

• exp has no control over which pp placed in which condition as the IV is pre-exsisting.
• Pp variables may have caused the change in DV acting as CV
• Researcher doesn’t manipulate IV cannot say change in DV was due to IV