Experimental design

• Independent groups

  Preform in 1 condition
• Independent groups +

  +No order effects

  +No DC
• Independent groups -

  -No control over participant variables, effect DV

  -Expensive
• Independent groups solution

  Random allocation, ensure each p has same chance of being in each condition
• Repeated Measure

  Preform in all conditions
• Repeated Measure +

  +Eliminates P variables

  +more economical

  +Change in DV down to manipulated IV, results more valid
• Repeated Measure -

  -Order effects

  -DC
• Matched Pairs

  Match Participants in each condition on certain V
• Matched Pairs +

  +Reduce DC

  +Avoids order effect
• Matched Pairs -

  -Impossible to completely match V

  -Time consuming matching P

  -Less economical
• Pilot Study

  •Small-scale trial run before the investigation

  •Allows for investigations real run to be modified

  •Saves time and money
• Double Blind

  •Neither participant nor researcher knows the aim

  •Prevent DC and Investigator effects
• Single Blind

  •Participants don’t know what aim is

  •Avoids DC
• Control Group

  •Group receives no change in IV or placebo

  •To see if cause and effect was due to IV within experimental groups