experimental design

• What is counter-balancing?

  • Balancing out conditions to even out bias
  • eg- 1/2 experimental group do condition A then B, other half do condition B then A, compare scores/performance between the groups
  • Makes sure order is distributed evenly across conditions
  • Makes each condition of the IV occur evenly
  • deals with order effects
• true or false? counterbalancing is not repeated measures

  FALSE- it is because you're still measuring performance of the two conditions for each pp
• describe each type of experimental design, evaluate them and suggest methods for dealing with limitations

  REPEATED MEASURES- each pp does both levels of the IV

  • 😊requires less participants
  • ☹️order effects- eg practise effect
  • ☹️demand characteristics- when they do the other level of IV, they may guess aims
  • improve- counterbalancing, or a cover story can be presented about the purpose of the test

  INDEPENDENT GROUPS- each pp only does one level of the IV

  • 😊reduces demand characteristics
  • 😊reduces order effects
  • ☹️pp variables
  • ☹️more pp to produce same data
  • improve- random allocation of pps to conditions

  MATCHED PAIRS- matching pps on key variables

  • 😊reduces demand characteristics
  • 😊limits pps variables
  • ☹️hard to match pps on all variables that need accounting for
  • ☹️time-consuming
  • to improve- limit variables you're trying to control, conduct pilot study to assess variables that need controlling