experimental design

• experimental design must make the hypothesis testable
• independant group design - means different participants in each group
• independant pro - no order effects
• independant con - participant variables - time
• repeated measures design - use same group twice
• repeated cons - order effects
• repeated pros - less participant variables
• matched pairs design - participants in both groups are matched on certain factors like age and iq
• matched pro - no order effects - participant variables
• matched cons - more participants - time consuming
• control groups - behaviour is not manipulated
• research should be highly controlled to limit the effects of extraneous variables
• random allocation - everyone has an equal chance of doing each condition
• counterbalencing - half of the participants with first task then second and half with second then first
• standardised instructions - ensure the experimenters act the same way with all participants
• randomisation - material is presented in a random order - avoid order effects
• pilot study - small scale study ran before to establish any issues