RM: experimental design + types

Question 1

experimental design

Answer 1

the different ways in which the testing of participants can be organised in relation to the experimental conditions

Question 2

independent groups

Answer 2

• 2 separate groups of ppts experience 2 separate conditions of experiment
• group 1 - control group
• group 2 - experimental group
• performance of 2 groups compared

Question 3

what are the four TYPES of experiment

Answer 3

laboratory, field, Natural and Quasi

Question 4

repeated measures

Answer 4

all ppts take part in all conditions of the experiment
- each ppt would experience control group condition + experimental group condition

Question 5

AO3 for matched pairs

Answer 5

• ppts can never be matched exactly
• time consuming + expensive
• Strength = no order effects/ demand characteristics

Question 6

matched pairs

Answer 6

• pairs of ppts first matched on some variables (I.e IQ)
• one member of the pair is assigned to condition A and other is assigned to condition B

Question 7

AO3 for independent groups

Answer 7

• ppts who occupy different groups are not the same
• results may vary bc of individual differences (ppt variables) (controlled using random allocation)
• strength - order effects are not a problem

Question 8

AO3 for repeated measures

Answer 8

• order effect problems - ppts repeat 2 tasks (create boredom/fatigue) (order = confounding variable)
• may work out study aim (Demand characteristics)
• Strength - fewer ppts needed

Question 9

Field experiments

Answer 9

experiment takes place in a natural setting
- IV is manipulated in a natural more everyday setting

Question 10

strengths of Laboratory experiments

Answer 10

• high control over extraneous variables - so can be sure that only IV is impacting DV (internal validity)
• replication is possible because of level of control

Question 11

counterbalancing

Answer 11

• method for controlling order effects in repeated measures design
• 1/2 ppts experience conditions in one order + 1/2 in the opposite order

Question 12

Limitations of Laboratory experiments

Answer 12

• may lack generalisability - conditions artificial
• ppts aware they are being tested - demand characteristics
  -not representative of real life (Low mundane realism)

Question 13

limitations of field experiments

Answer 13

• ethical issues - ppts unaware they are being studied so cant give consent
• loss of control of extraneous variables

Question 14

Laboratory experiments

Answer 14

• conducted in highly controlled settings
• researcher manipulates IV
• researcher maintains control of extraneous variables

Question 15

natural experiments

Answer 15

• researcher takes advantage of pre-existing IV
• called ‘Natural’ because variable would have changed even without researchers presence

Question 16

strengths of field experiments

Answer 16

• high mundane realism - natural environment
• ppts unaware they are being studied - higher external validity

Question 17

population

Answer 17

large group of people a researcher is interested in studying
- often called ‘target population’

Question 18

sample

Answer 18

group who take part in a research investigation
- sample is drawn from target population
- representative of target population - generalisable

Question 19

limitations of natural experiments

Answer 19

• natural occurring event is rare - difficult to generalise to other scenarios
• ppts not randomly allocated to experimental conditions

Question 20

Quasi experiments

Answer 20

• IV is based on existing difference between ppl (i.e. gender, race)
• IV is not manipulated, it simply exists

Question 21

strengths of quasi experiments

Answer 21

often carried out under controlled settings so same strengths as Laboratory experiments

Question 22

Limitations of Quasi experiments

Answer 22

cannot randomly allocate ppts to conditions so may be confounding variables

Question 23

strengths of Natural experiments

Answer 23

• high external validity - involve study of real life issues/problems as they happen