experimental designs

Question 1

list the types of experimental design and briefly describe each one

Answer 1

• independent group design - ppts are placed in separate groups/conditions
• repeated measure design - all ppts experience both conditions
• matched pair design - two groups of ppts are matched up based on key characteristics

Question 2

limitations of independent group design and how you’d deal with them

Answer 2

• researcher can’t control effects of ppt variables (deal with it through randomisation)
• more ppts required

Question 3

limitations of repeated measure design and how you’d deal with them

Answer 3

• order effects and demand characteristics (deal with it using counterbalancing)

Question 4

limitations of matched pair design and how you’d deal with them

Answer 4

• time consuming and difficult to match ppts
• large group required to ensure matched pairs on key variables
• isn’t always possible to control/match all ppt variables (some key variables may be ignored)
• deal with it using a pilot study to identify key variables

Question 5

strengths of independent group design

Answer 5

• order effects are not an issue
• ppts are less likely to guess the aims (demand characteristics)

Question 6

strengths of repeated measure design

Answer 6

• ppt variables are controlled (higher validity)
• fewer ppts needed (saves time)

Question 7

strengths of matched pair design

Answer 7

• order effects and demand characteristics are less of an issue