evaluation of repeated measures

• order effects can be present- boredom effects can occur, where pps do not complete the task properly because they get bored as they've already done it once before
• another order effect- practise effects, pps complete the task more effectively the second time because they have already done it before
• more cost effective than independent groups- need half the pps to breed the same amount of data, however takes longer as you have to complete the task, no individual differences as the same person experiences all conditions